Stony corals: how does kalk work? The lazy man's way to reef.

[sleepydoc]

Correct me if I'm wrong, but here's my understanding:

Adding Kalk to your ATO bucket keeps the ATO water saturated (~420?). The total amount of Ca added to your DT is simply 420 times the daily evaporation rate, which is basically a constant. The concentration of the DT will end up being a function of the rate of consumption by your corals and the rate of evaporation (= the rate Ca is being added). If you have a lot of corals, they will consume more Ca the levels will drop.

The 75 gal tank size 'limit' is simply because larger tanks will have more corals, and more consumption. A Ca reactor can add more per day because it actually adds it to the water circulating in the DT/sump, rather than waiting for it to evaporate.

Am I missing anything?

[jgsteven]

Originally Posted by Sk8r

Test your magnesium level in your tank at least every 2 weeks, but don't worry about your alk and cal. Those CANNOT fall so long as you don't let that bucket run out of water and kalk--- And as long as your tank doesn't run below 1200 on magnesium. That's your 'safe' zone for magnesium---1300 to 1200.

** Edit: Ahh, after thinking about this I understand now: RO/DI can only disolve so much kalk, so you can never add too much because this is less Ca and Alk than seawater with Mg at 1200+ can disolve. The only issue will be if your usage rate is lower than your evaporation rate * kalk saturation, in which case you need to dose super-saturated or 2-part.

Regards,

jgsteven

[jgsteven]

[QUOTE=Bnortz;19957300]
I obviously need to raise my alk, and somehow let the calcium and mag drop down.

What is my best option in stabilizing?QUOTE]


I was in this situation some time ago. I just did a couple water changes to get the parameters closer together over a couple of days, then dosed Alk (i.e., one part of the two part) to bring it up to where it needed to be.

I have heard you shouldn't just dose Alk when you have high Ca as it can cause a percipitate.

[koll12]

Originally Posted by Sk8r

By 'not measuring,' I mean that fresh water can ONLY dissolve a correct dose, which amounts to 2 tsp per gallon. You cannot get fresh ro/di to carry more than that, so you cannot overdose it. The rest will settle as a white slurry on the bottom. I have a 32 gallon reservoir, so I just dump in a pound of kalk now and again. I have my pump set up on eggcrate so it never sucks water from the bottom, where the slurry is. It will not overdose.

You should never, ever, ever dose freshly stirred kalk, because that will carry along bits of undissolved kalk, ie, the slurry. After mixing once, let it settle for 8 hours before using it, and never stir it again. A kalk stirrer is sold to the unwary, but is not a good thing unless you have sprung for a kalk reactor, and even so, ime, skip the reactor and use a bucket: it's cheaper, it doesn't break down 3 times a day. I had a 300.00 one and chucked it and two pricey stirrers in favor of a trashcan.




THere ARE kalk accidents, which amount to a topoff accident. It looks awful, cloudy white tank, etc, but your REAL problem is a) it's a topoff accident---fresh water has been added in a big overdose. Check your salinity. b) kalk comes in at ph 12, so if it was a really BIG topoff accident, ie, a real runaway, a teaspoon of Schweppe's bar soda per 50 gallons of tank water will start calming it down. Once mixed with salt water, the kalk very rapidly drops in ph, so if you do use that soda remedy don't overdo it, or the natural self-correction will combine with your fix and drop the ph too far. I've had accidents with it in a reef, no ill effects, no specimens and no fish lost. Of all dosing you can do, it's about the safest.





On dosing kalk , you said make it and let it sit or 8 hours. So are you making several different buckets all the time and then just pouring the mixed kalk water in the ATO ? What about the settlement in the bottom of those buckets that are mixed ? That doesn't cause a problem ? I guess I'm still kinda confused ? So doing kalk and having a calcium reactor are the same thing kinda ?

[troyman]

i always add a little vinager to the kaulk water i have no residue at bottom it completly dissolves

[BigCountry74]

anyone recommend a good mag test kit I can order online.

LFS wants 30-40 bucks for this kit!

!?!!?!

Great write up sk8r. This is where I am now, SPS and LPS. I bought a few frags of both last Saturday. The LPS frags are soft (brain and candycane) and they are hanging in there. The SPS were tree frags (hard stoneys?) and they do not look so good. Corals are all new to me so I eager to learn, experiment, hobby it out to get the stuff growing. I have hopefully built a tank that can support them, but I think I need to run it a few more months before I try any more coral.

[Lynxone]

So I have been getting my water parameters up to par over this last week and I am just about there (9dkh,1300mg,400calc). My top off water is kept in a 32g brute trash can downstairs in my basement and I run an rv water pump that i plumbed up through the walls that is activated by a switch in my fish cabinet (I plan to automate this with a float switch control in my sump.

I use this rv pump since a mag driven pump could not move water up from my basement. My question is this:

Water comes out of my feed line for top off at about 2-3g per minute into my 20g sump. My display tank is 75g. If I simply add kalk to my top off water, will I be dosing it too fast into the sump? If I adjust the float switch in my sump (that i am installing this week) so that it activates frequently without letting too much evap occur, is this enough control or do I need to build some sort of drip system to prevent over-dosing the kalk?

[Sk8r]

The evaporation rate of a tank is not decreased by feeding it water. Eg, my 54 evaporates about a gallon a day, every day. I use a float switch in my sump to keep the water level constant. It connects, electrically, to a Maxijet 1200 in my topoff bucket (actually a 32 gallon barrel.) This Maxijet sits on a piece of eggcrate jammed into the flexible barrel so it does NOT sit on the bottom where the undissolved kalk lies. It sits midwater, and sucks up only well-dissolved kalk. The Maxijet has a half-inch exit hose. Inside this hose, on the end, I inserted a locline connector and hose-clamped it into place. I then inserted a locline hose, a little 1/4" hose (exterior diameter) which runs to my tank. It's a fairly sensitive float switch: when the evaporation totals a couple of tablespoons (90 gallons of water in the system) it signals the pump so that the pump shoots a couple of tablespoons of kalkwater in, which raises the system water level, which causes the float to rise, and cut off the Maxijet. This is a 'sealed' float switch, meaning the bobber is in a cylinder a snail can't get into. I got it from autotopoff.com, not very pricey compared to some systems.

I add ro/di to the barrel about once every couple of weeks. I unplug my topoff pump overnight, to let the kalk settle from the agitation it gets from having new water dumped in. By morning the kalkwater is ready, with my never having physically stirred it. And I just plug the topoff pump back into the wall and I'm good for another two weeks.

With this in place, and good lighting, my tank grows euphyllias in great excess---I was just answering another thread wondering if a popped head of frogspawn can regrow its base. Yes. In my tank, well-supplied with calcium, it will. I had a tanksitter have a problem, some of my corals popped heads (coral heads came loose and settled like little anemones) and they have not only regrown a base, they are now new colonies. The amount of calcium these lps stonies consume daily is quite, quite amazing...and I don't think enough hobbyists realize how quickly these corals can deplete their tank of calcium. Before I started using kalk---I was testing and dosing calcium daily, and that stuff in the jar was getting really expensive, not to mention the test kits. Now I can be sure that my corals are getting all they need. Now, mind, I'm a 54g tank---but if you've got a 75 or larger as crowded with coral as mine, you may find kalk doesn't keep up. This is when you go to the vinegar option, because vinegar will cause more kalk to dissolve, ie, it goes in fast. But TEST! don't just do it and hope. Then if you're a 100g with lots of coral, you will ultimately need a calcium REACTOR, which uses an injection of co2 gas from a cannister to force calcium to dissolve---and when you get a mega-tank, who knows, you'll have to find ways to get it to happen faster and faster. At that point, read the accounts of the Tanks of the Month and figure out what those guys are doing for calcium supplement.
The way the ocean does it---its surf hammers dead coral to bits and it dissolves it and limestone rocks. It's been at this for gazillions of years, and it's large, and it keeps up. Your little finite tank doesn't have this resource, so you've got to do it: the chemistry still says that water will carry that proportion of calcium happily---but! if your corals are sucking it up from the same old 'tired, sucked-dry' water, going round and round and round, you've got to make up the deficit of a lively ocean which just sends the Humboldt Current past, fully charged with calcium. That's why we tank-keepers devised means of constantly replenishing our 'tired' water with fresh calcium, and clever tricks to get more and more into it. The more corals you have, the more they eat: ie, the kalk can supply the appetites of corals you can fit into 'little' tanks, but when your reef gets bigger, you're going to be feeding not 20 to 30 corals, but a hundred---and your little kalk barrel is not the Humboldt Current. Does that make sense? THAT's when you have to figure how to give them more and more and more as they keep building skeletons.

When I was in grade school, they taught us that coral reefs grow an inch a year. Ha! They are FAR hungrier than that. The tank I show above started with three little 3-head corals, and since corals double in size every few months, if thoroughly happy, you can get pretty crowded pretty quickly.

[w16227]

Originally Posted by Augustus

Just curious, I know sk8r said he tossed his but if its as simple as dumping kalk into your topoff water, why use a reactor?

I can give you a quick overview of the kalk reactor....

Kalk reactors give you separation between the kalkwater mix and your topoff pump. I run a PM Kalk reactor on my 125 - I have a water bucket that is kept filled with ro/di - and then the reactor filled with ~ 1/2 a large can of the kalk power at a time. The topoff pump feeds a line into the reactor (stop valve to prevent backwash) then the reactor feeds the tank. The reactor has a pump to stir the kalk at specified intervals (I have a controller managing this).


Benefits of a kalk reactor -

Kalk is sealed. PH of the slurry is high - and can be somewhat messy. The PM system is sealed so the mix is not accidentally exposed by the stray pet or child poking around. This also helps to extend the life of your topoff pulp. The high PH of the kalk mix can really bring down a pumps lifespan. I was using aqualifter pumps - and for a while had a bad stop valve so some of the kalkwater was back-filling into my topoff bucket (water levels caused a siphon to the kalk reactor at times). Pump gave out after like 8 months (I was LAZY in fixing the issue). With a good stop valve- more than a year for the pump.

Stirring - since you can dump a lot more of the kalk mix into a reactor - you also can have an element to mix up the batch to limit clumping. The PM has a max-jet pump that is directed at the bottom of the chamber. I usually run this about 5 minutes a day. Of course - this is made more necessary by the reactor itself - adding directly to topoff tank is usually done in smaller batches of kalk mix so you do not have to worry about clumping as much.

Plumbing - the PM reactor water inlet is at the bottom of the reactor - taking water for the display tank from the top. So the water flows upward You also are consistently pumping the fully saturated water into the tank, leaving teh slurry at the bottom of teh reactor. A setup like sk8tr has - you have to keep the pump elevated in the topoff tank so you do not pump particulate into your tank. I do not have a large topoff bucket (like 5 gal) - so if I tried the direct method, I would be adding topoff water every day (maybe more).


So - does anyone really need a reactor? Probably not for smaller tanks, but for larger ones (I have a 125g) - they help with making the process simpler with less time to maintain (you can add a LOT of the kalk into the reactor at once).

They also require a little more control than just adding to topoff water. If you use a stirrer - you need to make sure the topoff pump is not active at the same time - and even longer as you want some settling before you run the pump. The PM guards somewhat against this - as the "white" cloud during stirring is at the bottom half of the reactor chamber (the water to the tank feeds from the top) - but this is still a concern as you will see in a moment -


Can there be problems - YOU BET!

The ability to dump a couple months worth of kalk powder into a reactor does not mean that you can stop paying attention. You still need to refill these things. I have had great success with my reactor - but yet having this fueled my own laziness! Twice I have had mini "coral" crashes caused by not recognizing when I needed to fill the chamber (the reactor is not in plain sight). Having good growth told me things were "ok" - so I was not regular testing for CA and ALK. While corals can grow and survive with lower levels - what they really hate is RAPID swings. Once the kalk is gone - a demanding tank can really strip away the needed alk/ca and you are fighting the uphill battle to get things stable again.

The other end - you need to take care to remember that the more automated you make your system - the more issues you may cause yourself! So - established earlier that I can be lazy with some maintenance items. Sometime I will let my topoff bucket go low. Once - the sump was probably a gallon low so (topoff bucket dry), so I refill it.

I did not notice that the kalk stirrer had just finished running. So - even though the reactor draws water from the top - I added in a lot of the particulate in the water column as I was pumping a lot more water back into the system than is normal. Later that night - foxface in distress and I saw that the tank PH had JUMPED to 10 earlier after the topoff water was added. Was back at 9 at the time I noticed the fish which was almost lights out time. I was patient as the PH drops at night - did not want to over-correct and crash the PH. Next day - fox was fine and PH back to normal. BUT - will never let that mistake happen again (letting the topoff cover too much evap at once).



So for kalk - adding to topoff water or using a reactor are both great ways to help maintain ALK and CA. Simplest with more day to day maintenance is adding to the topoff water bucket.

Less maintenance intensive but more expensive to set up is a reactor. Do NOT think it is foolproof as this fool can attest - but I would think that this is the preferred method for larger tanks.


Later

[Sk8r]

Thanks for that, w16----
Let me clarify: there are 2 kinds of calcium-providing reactors---besides the method in which you put kalk powder straight into your topoff. Kalk reactors have some drawbacks: they were not for me---I had a line come loose and spew kalk over my entire basement floor, and I broke 2 eighty-dollar lab stirrers trying to make mine work. Because I have plenty of room, it's easy for me to make up a huge amount of kalkwater (32 gallons.)

But say that you're in an apartment and have no place to put a topoff bucket of any size: you can disguise it as a potted palm, under a decorative basket with the bottom cut out, or put it in a nice Moroccan side cabinet, but ultimately, hiding a big bucket with a locline coming out of it is not easy in every situation. So---the kalk reactor. It's fed from your topoff bucket, but it's hideable, and you can refill the bucket multiple times before you have to mess with refilling the kalk reactor. It consists of a clear 4" wide tube with some lines coming in and out, and its whole job is to let water from your reservoir mix with the load of kalk it's got. Because the water doesn't come in with any force, there is a stirrer that cuts on for about one minute a day and kicks up the kalk a bit. I'm real critical of the stirrer I had---and swear if I had to do it again, I'd put a tiny water line from a pump on a timer and just shoot one 30 second burst of water into the slurry at the bottom (which would kick it up enough) and be done. Rube Goldberg, but I have a real detestation of stirrers. I understand there are nice stirrers that behave much better, however. Ask around. But if you have a very limited space and don't want to mess with powder in your living room---this may be a good, though pricey, option for you. You could also make one, out of the parts described above. You just need to seal it: kalkwater doesn't like air. [ It forms a 'skin' which doesn't hurt anything, but is kind of nasty. A long strip of foam rubber around your bucket rim, under the lid, can let hose and cords out, and still keep your kalk air-free.]

The CALCIUM reactor is larger and more complicated. You have the usual ro/di bucket, but from there, the water hose goes to another clear cylinder, full of coral rubble and little calcium briquettes which you buy. Into this goes the ro/di water, but to MAKE the ro/di water dissolve those briquettes and rubble, you have another line, this one bringing in carbon dioxide gas from a gas cylinder about a foot high, with a regulator atop it that controls the flow, and a little dial-able device that counts how much co2 you're feeding into that reactor, which affects the ph, which affects how aggressively the water dissolves calcium and how much it carries. If you get the picture that it's larger than a kalk reactor, yes; the whole thing takes up some room; and there is a learning curve in which you figure where to set the inflow of gas to get the right calcium reading in your tank.

Understand that one of these is not BETTER than the other. It's just that the size of tank, your number of corals, and the size of space you've got to install stuff dictate which of these three ways of feeding your stony corals. And, let's add, for nano's, the fourth, the spoonful by spoonful method, which works fine for the very small tanks and for larger tanks taking their first steps toward a reef. The goal of all these methods is to keep injecting calcium into your tank faster than stony coral can eat it. You hear a lot about feeding your corals---but remember the main thing stony corals eat is calcium---it builds their bony structure, and piles up under them as they build 'reef'; and it fuels any contractile tissue that expels and intakes water; it builds shells on clams (another calcium-hungry creature); and builds fishy bones and fuels their muscles. These creatures depend on salt in the water they continually drink---but they also very heavily depend on the active consumption of calcium, which supports their bodies and enables movement.

So any time you hear someone asking what to feed his stony coral---you can say, in most basic terms, light (provides basic sugars, via the zooxanthellae, the color in its tissue) and a lot of calcium. The hobbyist that brings home a coral and watches it slowly fail---what's happened? Corals have a response to adverse conditions: they tuck in and 'sleep,' waiting for better conditions. Very frequently a new coral comes in stressed and starved from fragging, then shipping, and if it finds no great supply of what it needs in the new location it just goes on sleeping its way to its eventual demise.

When a coral hits 'good' water, good light, and a good temperature, it opens up fairly readily, because you've just fed it and its first little tendril extended to sample the environment has gotten a taste of abundance out there. If it's alive, it'll start sipping, then gather the strength to unfurl. Success with corals is basically just giving them a chance to do that.

[MaxxedMan]

[QUOTE=BigCountry74;19982055]anyone recommend a good mag test kit I can order online.

LFS wants 30-40 bucks for this kit!
QUOTE]

http://www.bulkreefsupply.com/store/...-ca-kh-mg.html

$50 but you get all 3 tests

[Sport507]

I use this one as many others on this site do.

http://www.bulkreefsupply.com/store/...-test-kit.html

I have not heard any bad reports on Red Sea and that sets you up for the top 3 Chem. test.

[MuzzleFlash]

Great thread, there is a ton of useful info here. Thanks Sk8r.

[nanojg]

Originally Posted by Sk8r

It's a fairly sensitive float switch: when the evaporation totals a couple of tablespoons (90 gallons of water in the system) it signals the pump so that the pump shoots a couple of tablespoons of kalkwater in, which raises the system water level, which causes the float to rise, and cut off the Maxijet. This is a 'sealed' float switch, meaning the bobber is in a cylinder a snail can't get into. I got it from autotopoff.com, not very pricey compared to some systems.
.

Your auto top off float switch is that sensitive? Weird, so it must come on about once every 10 minutes then (figure about a gallon of water a day)? Is the float switch in a very small sump compartment? Mine is in a 40 gallon plastic sump and turns on for well over 2 tablespoons, probably a cup or more at least at a time. I dont think id want my ato on/off every 10 minutes

[Sk8r]

Certainly no more than a quarter of a cup when it cuts on and off. It's in a 30 g sump.

[John_B]

If I manually top off directly into the DT daily, how much kalkwater would I be safe to add at once if I mix at 1 tsp per gallon of water?

[nanojg]

http://reefkeeping.com/issues/2005-01/rhf/index.php#5

a good article on limewater, from the article:

" Delivering a small amount of limewater all at once. Adding 1.25% of the aquarium’s volume (1.25 gallons of limewater per 100 gallons of aquarium water) as saturated limewater all at once raises the pH by 0.6 to 0.7 pH units. Such an increase is clearly too large. Adding a smaller portion all at once can, however, be acceptable. Adding, for example, 0.25% of the aquarium volume (0.25 gallons or 1 L of limewater per 100 gallons of aquarium water) will raise the pH by only 0.1 to 0.2 pH units. Unless the pH is high (>8.4) before the addition, that amount is likely acceptable. The other concern with all-at-once dosing is that the local pH in the area of the addition will rise considerably higher than the values above. So dosing must be done far from living organisms, and in high flow areas that will facilitate fast mixture. In some aquaria, such restrictions make all-at-once dosing of limewater prohibitively risky to living organisms."


So if you added 0.5% of the aquarium volume at 50% saturated limewater (1 tsp per gallon) it would raise ph about .1-.2 which is safe.

[w16227]

Originally Posted by Sk8r

Thanks for that, w16----
Kalk reactors have some drawbacks: they were not for me---I had a line come loose and spew kalk over my entire basement floor, and I broke 2 eighty-dollar lab stirrers trying to make mine work. Because I have plenty of room, it's easy for me to make up a huge amount of kalkwater (32 gallons.)t.

some stuff snipped -

There are also some very simple reactors.

When starting - I bought the Tunze Osmolator topoff - they had a kalk attachment. Pretty much a separate chamber that the topoff line (like a refrigerator water line) pushed water through. Sort of like what Sk8r has - just not directly added to the topoff bucket. This worked well with little chance of a mess (you could remove the chamber with quick connects) - but was not that useful for a larger tank as I had to refil the chamber a lot. Even with quick connects - it was just too often.

Note on stirrers - echo Sk8r - some are known to be troublesome. One of the reasons I like the PM model - in that the water is forced upward through the kalk "slurry" helping keep the saturation level - and that the stirrer is not really a stirrer at all - but a powerhead pump (Maxi-Jet 400).

The pump needs replacement every so often, but a MJ400 is cheap and I have not had to replace mine in 3 years. It has just started to rattle some, so wither needs a good vinegar soak - or the impeller might finally be shot.

[SKurj]

Good thread, I think I am almost there, today's readings:
Salinity 1.026
Temp 79
Alk 6.9
Mg 1370
Ca 400
Nitrate 10 (big drop this week!)

I am going to add some alk buffer each day the next few days and retest, as soon as it gets close to 9.3 I'll add some kalk to the tunze.

[Sk8r]

You need to add a bit of calcium after your alk gets up to level. Once you have it, your mg will lock all 3 in relationship. You might want to add a bit of freshwater to lower that salinity .001, to 1.025---gives you a little wiggleroom in both directions.

[kingevil]

Originally Posted by Sk8r

I add ro/di to the barrel about once every couple of weeks. I unplug my topoff pump overnight, to let the kalk settle from the agitation it gets from having new water dumped in. By morning the kalkwater is ready, with my never having physically stirred it. And I just plug the topoff pump back into the wall and I'm good for another two weeks.

so, do you only stir when you add new kalk? if there is still residue on the bottom of your ato res, and you add new water, do you still have to shut the ato pump off overnight? since i've never done this, i'm not sure how much gets stirred up when you add new ro/di water.

[pfcreed]

thanks so much for explaining this

[Sk8r]

Only when you add new water. Leave the ATO off 12 or so hours the first time, which should be long enough to let the white stuff settle back to the bottom. THat filmy but clear water's what 'settled kalkwater' looks like. Now turn on your ATO. Once you know what settled kalkwater looks like (only slightly filmy) just have a look before you go to bed and just switch your ato on if it looks clear enough. If not, wait til morning. It's not going to hurt anything if it has to do a little catchup from overnight.

[kingevil]

if my numbers are just below where i want them, can i start adding kalk (pickling lime) now, to keep the numbers from falling further, and then add supplements to bring up those numbers?

[Sk8r]

Kalk itself is not good at raising numbers. Stop the kalk drip temporarily and use hand-dosing of calcium, mg, alk buffer supplements to bring it perfectly to level, then start your drip and it should hold exactly there. Always raise mg first, because that's the prop that holds the other two up. Mg first, then alk, then cal.