Importance of magnesium in a reef.

hamiltonguy · 02/07/2009, 04:41 PM

Ok, so after alot of reading I figured that magnesium was an important element to supplement in a reef tank. However, I went to my LFS last night looking to buy a magnesium test kit and a supplement and the guy there (very nice guy btw, talked to me for an hour about reef tanks and his experiences) told me that there is no need to supplement magnesium in a reef. So, at first I was a little iffy about believing but he told me how they keep their systems, showed me everything they does and their sump room behind their tanks.

On the other hand I've seen tanks where people have automated dosers dedicated to magnesium, among other things of course.

As far as I know, scientists do not yet know why corals need magnesium and how they use it. All I've come to know is that coral need magnesium in order to use calcium and alk in the tank.

So my question is, should I be dosing magnesium? If you provide any possible reasons or benefits to dosing, that'd be great

.

dwd5813 · 02/07/2009, 04:58 PM

my understanding, limited as it is, is that proper magnesium levels will prevent precipitation of calcium carbonate at the levels where we as aquarists aim to keep it. in other words, it raises the saturation point of calcium and allows the proper balance between calcium and alkalinity at higher levels than otherwise attainable.

Sk8r · 02/07/2009, 05:20 PM

If your mg isn't 3x your calcium, your calcium and alk will fall, and no, if you have corals (definition of a reef) of the stony persuasion, they will take more mg than your salt mix has. You can replenish by water changes once weekly---c'mon, fess up, how many of us do it EVERY week---BUT---some salt mixes are low in mg in the first place. I have to supplement it for some rapidly growing LPS. Your lps may not be wholly wrong If they are thinking ONLY of softie corals, and absolutely regular water changes, but even then, bad idea: your mg will sooner or later deplete and then your alk will fall, your fish will be unhappy, and you'd be left wondering why you can't raise your alk no matter how much buffer you add.

Whys · 02/07/2009, 05:31 PM

Thanks for this Sk8r.

marineaddict · 02/07/2009, 05:36 PM

Quote:

Originally posted by Sk8r
If your mg isn't 3x your calcium, your calcium and alk will fall, and no, if you have corals (definition of a reef) of the stony persuasion, they will take more mg than your salt mix has. You can replenish by water changes once weekly---c'mon, fess up, how many of us do it EVERY week---BUT---some salt mixes are low in mg in the first place. I have to supplement it for some rapidly growing LPS. Your lps may not be wholly wrong If they are thinking ONLY of softie corals, and absolutely regular water changes, but even then, bad idea: your mg will sooner or later deplete and then your alk will fall, your fish will be unhappy, and you'd be left wondering why you can't raise your alk no matter how much buffer you add.

I swear every post of yours is right on!! I honestly just love how you take the time to explain so much to so many people.

I see you are a writer - send me anything you have written, I know it will be a good read.

Sk8r · 02/07/2009, 05:40 PM

You're very kind.

eros · 02/07/2009, 06:14 PM

I also went looking for a Mg test kit and got the same advice as you. So, I never bought a kit. Then I got a bucket of salt that had 400ppm Mg but because I didn't have a test kit I used 90% of the bucket before I finally ended ordering one online and discovered that was the problem. It almost crashed my tank, everything in my tank looked horrible and I had no idea why. I brought my Mg up to acceptable levels and now my tank is thriving. Buy a testkit, even if you have to get one online. Many manufacuteres are low in Mg and the problem goes largely unnoticed because most people dont test for it.

hamiltonguy · 02/07/2009, 11:35 PM

Thanks for all the info guys. As I went through more tank setups online, I think I will buy a mg test kit and supplements if I need it; better safe than sorry I guess.

As for water changes, I do mine every weekend since I don't see my tank during weekdays because I go away fro university.

So far, I only have two corals. I'm waiting for my tank to mature for a couple more months so I can add an anemone before I start stocking my tank. As of yet my two corals, torch and elegance, are both thriving. The elegance has grown a lot since I got it and I think I've only had it for probably 3 weeks or a month (can't remember exactly). I think that's why I've been able to get away with dosing Mg.I know my Mg levels aren't optimum because I use IO salt and it doesn't contain the amount require for a reef.

But again, thanks for the advice, 'preciate it guys.

xJake · 02/08/2009, 12:03 AM

I realize this is a bit suggestive, but it explains this topic extremely well. Basically, I like to use the following metaphor the describe the relationship between Magnesium and Calcium/Alkalinity...

Think of calcium as a male, and alkalinity as a female. They are naturally attracted to each other when dissolved in water, and when they bond they achieve a state of "happiness" as calcium carbonate. These two molecules look for ways to bond and form calcium carbonate, and they are constantly trying to do so. Think of magnesium as a sort of "chaperon" (or perhaps "The Catholic Church" if you will) in this case and coral calcification as almost like "marriage". Magnesium prevents calcium and alkalinity from prematurely "bonding" before "marriage." Without enough magnesium (~3x calcium), any "unchaperoned" calcium and alkalinity can begin bonding wherever. This causes any extra calcium and carbonate (alkalinity) ions, that the magnesium can't "chaperon," to precipitate out of the water column. This usually occurs in areas of higher temperatures such as on heating elements or on the interior of pumps where the impeller friction causes excess heat. This mechanical precipitation lowers both your calcium and alkalinity levels without contributing to any actual coral growth. So, magnesium is important for maintaining these levels, and in turn it saves you money on supplements.

Basically, magnesium acts as a way to prevent unwanted calcium carbonate precipitation so that your corals can use it instead.

Whys · 02/08/2009, 10:17 AM

Jake, I was hoping you'd jump in on this one. Love your analogy, BTW.

iamwrasseman · 02/08/2009, 11:18 AM

wow that deep ................but true ,awesome ! are you a teacher ?just dont use the male female thing in class .

Sk8r · 02/08/2009, 11:29 AM

Great analogy.

Frankly, I think the whole alk/cal/mg thing is way undersold to FOWLR tanks and softie reefs. If you haven't got all 3, your water is NOT going to be as good as if you did, plus you're going to have a pita of a time getting your alk to hold steady, and neither fish nor softies are that happy with bum alk...softies more so, but why subject your fish to low alk, either? It's only my own crackpot theory, but if we all emphasized getting the Big 3 test kits right after the cycle, we'd see fewer diseased fish, dead fish, crashed tanks, and just not very great tanks. Yes, we should all do our water changes, but as I stated in my first post, salt mixes often scant magnesium. Well, if this goes on, and on, and on, despite your water changes, eventually you've got screwed-up water balance, and, again, IMHO, I don't think it's that great. Sure, there are fish that can't be kept in a reef (ie, you can't afford to feed them corals, or their waste-production exceeds what a reef can cope with, and they'll survive a little nitrate (more than they'd have to in the ocean)) but consequently (third IMHO) don't they deserve more, rather than less, help with their water quality?

Whys · 02/08/2009, 11:31 AM

Quote:

are you a teacher ?

He will be. Oh he will be.

Jake, someday you are going to have the most awesome parties on the block. You'll have to make your fortune from smart investing, or possibly an invention, but I've little doubt you will. Please think of me when the time comes.

hamiltonguy · 02/08/2009, 11:35 AM

Quote:

Originally posted by xJake
Think of magnesium as a sort of "chaperon" (or perhaps "The Catholic Church" if you will) in this case and coral calcification as almost like "marriage".

Lol, that gave me a good laugh :P. This "calcium carbonate," are you referring to coralline algae or just the white precipitate? (Probably a lame question for a science major :P. Even though I'm in 1st year, all the chemistry I took, I just took because I had to and needed a good mark. As for what happened in the class, i don't really remember alot of it).

Sk8r: Again thanks for the advice. As I stated I think the only reason I haven't come across problems and have been able to skimp on Mg is due my low bioload (2 corals and 4 fish; largest being ~1.5"-2"). And even then I see my calcium drop (~20-30ppm/wk) and my alk drop (~2dKh/wk).

As I read more and more online, it seems as if it would be just safer to monitor my Mg. I trust the LFS guy because he told me get him when I upgrade he'll help me set up the bigger tank. So far he hasn't suggested ANYTHING that I wouldn't need.

xJake · 02/08/2009, 12:28 PM

Quote:

Originally posted by hamiltonguy
Lol, that gave me a good laugh :P. This "calcium carbonate," are you referring to coralline algae or just the white precipitate? (Probably a lame question for a science major :P. Even though I'm in 1st year, all the chemistry I took, I just took because I had to and needed a good mark. As for what happened in the class, i don't really remember alot of it).

In this case, the calcium carbonate would be the white precipitate. It's the same stuff that jams up your water pumps and makes your heaters all crusty after awhile. This white precipitate is due to the mechanical (physical) formation of calcium carbonate rather than the more desired biological formation (coral calcification, or as you mentioned, coralline algae growth, etc.).

Whys: I'm definitely considering becoming a teacher, but I still have a few more years to decide. Thanks for compliment.

dwd5813 · 02/08/2009, 12:32 PM

excellent analogy.

the calcium carbonate that is mentioned is not coralline algae, but rather your second conclusion, a white precipitate.

Brent RH · 02/08/2009, 12:45 PM

I don't have a mag test kit. I use Tropic marin reef blend. So your saying the reason for always having to add cal and alk is because my mag. is not were it should be?
Oh and I've seen a chart posted that shows a Mfg of salt and what Cal and alk levels come at. How about a chart that shows mag levels too. How is mag measured and what should ideal levels be? So if I get Mag to right level...my cal and alk will regulate them selves. I need more explaining please!!!!

Sk8r · 02/08/2009, 01:07 PM

The Great 3!
Alk should be 8.3-9.3, calcium 400-420, and mg should be a bit over 3x your desired calcium level.

Many things use calcium: coralline, snails, even fish (bones). And it precipitates, as discussed above. Everything gets used. The Great 3 are the 'currency' of the reef, the transaction on which just about everything operates.

And the Great Stabilizer is magnesium, that mysterious, silent chemical that holds everything steady. You need a mg test kit, and should run it maybe once a month, or whenever you see a drop in your alk. On the other hand, if you keep it up and keep supplementing, you won't SEE a drop in your alk.

One of the best ways to do this in a stony coral tank with a sump is to drip kalk via your automatic topoff: first you dose with regular supplements to get everything 'set' at the levels I set out above. If you try to hand-dose a reef, you end up dumping huge amounts of supplement in. But in the kalk method----
you dump kalk powder (Mrs. Wages' Pickling Lime) into the ro/di in your topoff reservoir (2 tsp per gallon) stir it, let it set for 24 hours, and then let the automatic topoff (ATO) deliver it in the usual way. Result? Perfectly steady chemistry: alk and cal will stay up until the mg runs out. Keep testing and supplementing magnesium (NOT provided in the lime) and it will hold steady until the water runs out---keep supplementing mg and adding more ro/di ANd more lime, and you can keep that game going for months without a glitch. When it finally gets out of balance or you just need to do some cleaning, re-set all your levels, and restart your drip as given above. Easiest, cheapest way to supplement your tank and hold the levels steady. The 2 tsp is for stony corals.

Brent RH · 02/08/2009, 01:22 PM

A specific brand of mag to search out. What is the creme of the crop? I'm adding cal and alk weekly. Is this a give away that my mag is not in check? How about a chart that shows all of its factory chemistry?

Brent RH · 02/08/2009, 01:24 PM

Oh BTW I've been trying to keep my cal closer to 500. Is this to high? Its what I read to be desired level online...

xJake · 02/08/2009, 01:33 PM

Quote:

Originally posted by Brent RH
A specific brand of mag to search out. What is the creme of the crop? I'm adding cal and alk weekly. Is this a give away that my mag is not in check? How about a chart that shows all of its factory chemistry?

The latest "hot product" seems to be magnesium chloride hexahydrate (flake) by Dead Sea Works. The original product was Mag-flake by Dow Chemical, but they have changed their manufacturing process to include excessive amounts of bromine (which can cause issues in the reef aquarium). DSW doesn't use this excess bromine, so it is considered to be more "reef-safe." You should mix this in a 5:3 ratio with magnesium sulfate (epsom salts) in order to maintain a proper chloride:sulfate ratio. This allows you to avoid the addition of excess sulfate or chloride ions from using each salt separately - as the sulfate and chloride ions almost neutralize each other in the correct ratio.

Most of the products specifically designed for aquariums are just repackaged versions of these bulk salts. The only product I know of that isn't is Kent Tech-M. Kent claims they have the magnesium in "ionic" form in their Tech-M product; which really doesn't make much difference in terms of our needs. Ionic or molecular (salt-form), our animals will still use it the same, and it will still serve the same function.

Weekly supplementation sounds fine (depending on your individual coral bioload of course). Corals do actually use calcium and alkalinity and cause it to steadily decline, so it does need to be replaced pretty regularly. If your levels are dropping drastically on almost a daily basis, then I would be concerned, but weekly supplementation is fairly normal IMO.

Quote:

Originally posted by Brent RH
Oh BTW I've been trying to keep my cal closer to 500. Is this to high? Its what I read to be desired level online...

You can keep your calcium that high, but there isn't much advantage. I would suggest maxing out calcium at 450ppm (the required magnesium level begin ~1350ppm) and alkalinity at ~3.5meq/L. These levels will constantly fluctuate though, so there is a bit of wiggle room (actually there's a lot of wiggle room, but it's best to keep your levels stabilized).

iamwrasseman · 02/08/2009, 06:10 PM

i dont want to get off the subject but you seem a bit knowledgable so here goes .i have raised my mag level to 1650 in order to kill off hair algea and it has worked great along with a probuct called algea fix .is there any problems with the mag being this high or will all be okay at that level and are there any long term effects of this raised level ?thanks

cloak · 02/08/2009, 07:06 PM

FWIW, my tank lasted almost nine years without paying any mind to magnesium. Guessing the tank was getting all it needed from the regular water changes.

Brent RH · 02/08/2009, 07:45 PM

Quote:

Originally posted by cloak
FWIW, my tank lasted almost nine years without paying any mind to magnesium. Guessing the tank was getting all it needed from the regular water changes.

How about your alk and cal. did they move all over. Or were you not doing a reef?

cloak · 02/08/2009, 07:57 PM

Alk was steady at 8. Calcium, I don't know. I used tap water for almost nine years and the coralline grew rapidly. Didn't see any reason to test the calcium. The chemistry wasn't broke. It worked.

02/07/2009, 04:41 PM	#1
hamiltonguy Registered Member Join Date: Jan 2009 Location: Hamilton, Ontario Posts: 906	Importance of magnesium in a reef. Ok, so after alot of reading I figured that magnesium was an important element to supplement in a reef tank. However, I went to my LFS last night looking to buy a magnesium test kit and a supplement and the guy there (very nice guy btw, talked to me for an hour about reef tanks and his experiences) told me that there is no need to supplement magnesium in a reef. So, at first I was a little iffy about believing but he told me how they keep their systems, showed me everything they does and their sump room behind their tanks. On the other hand I've seen tanks where people have automated dosers dedicated to magnesium, among other things of course. As far as I know, scientists do not yet know why corals need magnesium and how they use it. All I've come to know is that coral need magnesium in order to use calcium and alk in the tank. So my question is, should I be dosing magnesium? If you provide any possible reasons or benefits to dosing, that'd be great .

02/07/2009, 04:58 PM	#2
dwd5813 Registered Member Join Date: Oct 2005 Location: 813 Posts: 2,827	my understanding, limited as it is, is that proper magnesium levels will prevent precipitation of calcium carbonate at the levels where we as aquarists aim to keep it. in other words, it raises the saturation point of calcium and allows the proper balance between calcium and alkalinity at higher levels than otherwise attainable. __________________ order some golf shoes, otherwise we'll never get out of this place alive. what can i say? in dog beers, i have only had one. - dublo8 Current Tank Info: 40B aiptasia farm

02/07/2009, 05:20 PM	#3
Sk8r RC Mod Join Date: Feb 2006 Location: Spokane WA Posts: 34,628 Blog Entries: 55	If your mg isn't 3x your calcium, your calcium and alk will fall, and no, if you have corals (definition of a reef) of the stony persuasion, they will take more mg than your salt mix has. You can replenish by water changes once weekly---c'mon, fess up, how many of us do it EVERY week---BUT---some salt mixes are low in mg in the first place. I have to supplement it for some rapidly growing LPS. Your lps may not be wholly wrong If they are thinking ONLY of softie corals, and absolutely regular water changes, but even then, bad idea: your mg will sooner or later deplete and then your alk will fall, your fish will be unhappy, and you'd be left wondering why you can't raise your alk no matter how much buffer you add. __________________ Sk8r Salinity 1.024-6; alkalinity 8.3-9.3 on KH scale; calcium 420; magnesium 1300, temp 78-80, nitrate .2. Ammonia 0. No filters: lps tank. Alk and cal won't rise if mg is low. Current Tank Info: 105g AquaVim wedge, yellow tang, sailfin blenny,royal gramma, ocellaris clown pair, yellow watchman, 100 microceriths, 25 tiny hermits, a 4" conch, 1" nassarius, recovering from 2 year hiatus with daily water change of 10%.

02/07/2009, 05:40 PM	#6
Sk8r RC Mod Join Date: Feb 2006 Location: Spokane WA Posts: 34,628 Blog Entries: 55	You're very kind. __________________ Sk8r Salinity 1.024-6; alkalinity 8.3-9.3 on KH scale; calcium 420; magnesium 1300, temp 78-80, nitrate .2. Ammonia 0. No filters: lps tank. Alk and cal won't rise if mg is low. Current Tank Info: 105g AquaVim wedge, yellow tang, sailfin blenny,royal gramma, ocellaris clown pair, yellow watchman, 100 microceriths, 25 tiny hermits, a 4" conch, 1" nassarius, recovering from 2 year hiatus with daily water change of 10%.

02/07/2009, 11:35 PM	#8
hamiltonguy Registered Member Join Date: Jan 2009 Location: Hamilton, Ontario Posts: 906	Thanks for all the info guys. As I went through more tank setups online, I think I will buy a mg test kit and supplements if I need it; better safe than sorry I guess. As for water changes, I do mine every weekend since I don't see my tank during weekdays because I go away fro university. So far, I only have two corals. I'm waiting for my tank to mature for a couple more months so I can add an anemone before I start stocking my tank. As of yet my two corals, torch and elegance, are both thriving. The elegance has grown a lot since I got it and I think I've only had it for probably 3 weeks or a month (can't remember exactly). I think that's why I've been able to get away with dosing Mg.I know my Mg levels aren't optimum because I use IO salt and it doesn't contain the amount require for a reef. But again, thanks for the advice, 'preciate it guys. __________________ Knowledge, the only thing that's cheap in this hobby. Current Tank Info: 75G, RO NW-150 Skimmer, MP40W, MP20, 48" 4x54W TEK light, Mag 9.5, TLF 150 Bio Pellet Reactor, JBJ ATO

02/07/2009, 05:31 PM	#4
Whys Moved On Join Date: Mar 2008 Location: Spokane, WA Posts: 3,263	Thanks for this Sk8r.

02/07/2009, 06:14 PM	#7
eros Registered Member Join Date: Nov 2004 Location: Reno, Nevada Posts: 878	I also went looking for a Mg test kit and got the same advice as you. So, I never bought a kit. Then I got a bucket of salt that had 400ppm Mg but because I didn't have a test kit I used 90% of the bucket before I finally ended ordering one online and discovered that was the problem. It almost crashed my tank, everything in my tank looked horrible and I had no idea why. I brought my Mg up to acceptable levels and now my tank is thriving. Buy a testkit, even if you have to get one online. Many manufacuteres are low in Mg and the problem goes largely unnoticed because most people dont test for it.

02/08/2009, 12:03 AM	#9
xJake Registered Member Join Date: Nov 2006 Posts: 1,385	I realize this is a bit suggestive, but it explains this topic extremely well. Basically, I like to use the following metaphor the describe the relationship between Magnesium and Calcium/Alkalinity... Think of calcium as a male, and alkalinity as a female. They are naturally attracted to each other when dissolved in water, and when they bond they achieve a state of "happiness" as calcium carbonate. These two molecules look for ways to bond and form calcium carbonate, and they are constantly trying to do so. Think of magnesium as a sort of "chaperon" (or perhaps "The Catholic Church" if you will) in this case and coral calcification as almost like "marriage". Magnesium prevents calcium and alkalinity from prematurely "bonding" before "marriage." Without enough magnesium (~3x calcium), any "unchaperoned" calcium and alkalinity can begin bonding wherever. This causes any extra calcium and carbonate (alkalinity) ions, that the magnesium can't "chaperon," to precipitate out of the water column. This usually occurs in areas of higher temperatures such as on heating elements or on the interior of pumps where the impeller friction causes excess heat. This mechanical precipitation lowers both your calcium and alkalinity levels without contributing to any actual coral growth. So, magnesium is important for maintaining these levels, and in turn it saves you money on supplements. Basically, magnesium acts as a way to prevent unwanted calcium carbonate precipitation so that your corals can use it instead.

02/08/2009, 10:17 AM	#10
Whys Moved On Join Date: Mar 2008 Location: Spokane, WA Posts: 3,263	Jake, I was hoping you'd jump in on this one. Love your analogy, BTW.

02/08/2009, 11:18 AM	#11
iamwrasseman Registered Member Join Date: Oct 2008 Location: syracuse Posts: 7,003	wow that deep ................but true ,awesome ! are you a teacher ?just dont use the male female thing in class . __________________ This hobby certainly can put you in some weird positions ! Dave Current Tank Info: 40 freshwater,25saltwater 2000 gallons ,enough tanks for an army ?

02/08/2009, 11:29 AM	#12
Sk8r RC Mod Join Date: Feb 2006 Location: Spokane WA Posts: 34,628 Blog Entries: 55	Great analogy. Frankly, I think the whole alk/cal/mg thing is way undersold to FOWLR tanks and softie reefs. If you haven't got all 3, your water is NOT going to be as good as if you did, plus you're going to have a pita of a time getting your alk to hold steady, and neither fish nor softies are that happy with bum alk...softies more so, but why subject your fish to low alk, either? It's only my own crackpot theory, but if we all emphasized getting the Big 3 test kits right after the cycle, we'd see fewer diseased fish, dead fish, crashed tanks, and just not very great tanks. Yes, we should all do our water changes, but as I stated in my first post, salt mixes often scant magnesium. Well, if this goes on, and on, and on, despite your water changes, eventually you've got screwed-up water balance, and, again, IMHO, I don't think it's that great. Sure, there are fish that can't be kept in a reef (ie, you can't afford to feed them corals, or their waste-production exceeds what a reef can cope with, and they'll survive a little nitrate (more than they'd have to in the ocean)) but consequently (third IMHO) don't they deserve more, rather than less, help with their water quality? __________________ Sk8r Salinity 1.024-6; alkalinity 8.3-9.3 on KH scale; calcium 420; magnesium 1300, temp 78-80, nitrate .2. Ammonia 0. No filters: lps tank. Alk and cal won't rise if mg is low. Current Tank Info: 105g AquaVim wedge, yellow tang, sailfin blenny,royal gramma, ocellaris clown pair, yellow watchman, 100 microceriths, 25 tiny hermits, a 4" conch, 1" nassarius, recovering from 2 year hiatus with daily water change of 10%.

02/08/2009, 12:32 PM	#16
dwd5813 Registered Member Join Date: Oct 2005 Location: 813 Posts: 2,827	excellent analogy. the calcium carbonate that is mentioned is not coralline algae, but rather your second conclusion, a white precipitate. __________________ order some golf shoes, otherwise we'll never get out of this place alive. what can i say? in dog beers, i have only had one. - dublo8 Current Tank Info: 40B aiptasia farm

02/08/2009, 12:45 PM	#17
Brent RH Registered Member Join Date: Sep 2008 Location: central Minnesota Posts: 311	I don't have a mag test kit. I use Tropic marin reef blend. So your saying the reason for always having to add cal and alk is because my mag. is not were it should be? Oh and I've seen a chart posted that shows a Mfg of salt and what Cal and alk levels come at. How about a chart that shows mag levels too. How is mag measured and what should ideal levels be? So if I get Mag to right level...my cal and alk will regulate them selves. I need more explaining please!!!!

02/08/2009, 01:07 PM	#18
Sk8r RC Mod Join Date: Feb 2006 Location: Spokane WA Posts: 34,628 Blog Entries: 55	The Great 3! Alk should be 8.3-9.3, calcium 400-420, and mg should be a bit over 3x your desired calcium level. Many things use calcium: coralline, snails, even fish (bones). And it precipitates, as discussed above. Everything gets used. The Great 3 are the 'currency' of the reef, the transaction on which just about everything operates. And the Great Stabilizer is magnesium, that mysterious, silent chemical that holds everything steady. You need a mg test kit, and should run it maybe once a month, or whenever you see a drop in your alk. On the other hand, if you keep it up and keep supplementing, you won't SEE a drop in your alk. One of the best ways to do this in a stony coral tank with a sump is to drip kalk via your automatic topoff: first you dose with regular supplements to get everything 'set' at the levels I set out above. If you try to hand-dose a reef, you end up dumping huge amounts of supplement in. But in the kalk method---- you dump kalk powder (Mrs. Wages' Pickling Lime) into the ro/di in your topoff reservoir (2 tsp per gallon) stir it, let it set for 24 hours, and then let the automatic topoff (ATO) deliver it in the usual way. Result? Perfectly steady chemistry: alk and cal will stay up until the mg runs out. Keep testing and supplementing magnesium (NOT provided in the lime) and it will hold steady until the water runs out---keep supplementing mg and adding more ro/di ANd more lime, and you can keep that game going for months without a glitch. When it finally gets out of balance or you just need to do some cleaning, re-set all your levels, and restart your drip as given above. Easiest, cheapest way to supplement your tank and hold the levels steady. The 2 tsp is for stony corals. __________________ Sk8r Salinity 1.024-6; alkalinity 8.3-9.3 on KH scale; calcium 420; magnesium 1300, temp 78-80, nitrate .2. Ammonia 0. No filters: lps tank. Alk and cal won't rise if mg is low. Current Tank Info: 105g AquaVim wedge, yellow tang, sailfin blenny,royal gramma, ocellaris clown pair, yellow watchman, 100 microceriths, 25 tiny hermits, a 4" conch, 1" nassarius, recovering from 2 year hiatus with daily water change of 10%.

02/08/2009, 01:22 PM	#19
Brent RH Registered Member Join Date: Sep 2008 Location: central Minnesota Posts: 311	A specific brand of mag to search out. What is the creme of the crop? I'm adding cal and alk weekly. Is this a give away that my mag is not in check? How about a chart that shows all of its factory chemistry?

02/08/2009, 01:24 PM	#20
Brent RH Registered Member Join Date: Sep 2008 Location: central Minnesota Posts: 311	Oh BTW I've been trying to keep my cal closer to 500. Is this to high? Its what I read to be desired level online...

02/08/2009, 06:10 PM	#22
iamwrasseman Registered Member Join Date: Oct 2008 Location: syracuse Posts: 7,003	i dont want to get off the subject but you seem a bit knowledgable so here goes .i have raised my mag level to 1650 in order to kill off hair algea and it has worked great along with a probuct called algea fix .is there any problems with the mag being this high or will all be okay at that level and are there any long term effects of this raised level ?thanks __________________ This hobby certainly can put you in some weird positions ! Dave Current Tank Info: 40 freshwater,25saltwater 2000 gallons ,enough tanks for an army ?

02/08/2009, 07:06 PM	#23
cloak Moved On Join Date: Jul 2000 Location: Stockton, CA Posts: 14,854	FWIW, my tank lasted almost nine years without paying any mind to magnesium. Guessing the tank was getting all it needed from the regular water changes.

02/08/2009, 07:57 PM	#25
cloak Moved On Join Date: Jul 2000 Location: Stockton, CA Posts: 14,854	Alk was steady at 8. Calcium, I don't know. I used tap water for almost nine years and the coralline grew rapidly. Didn't see any reason to test the calcium. The chemistry wasn't broke. It worked.