Let's talk about Alkalinity, Calcium and Magnesium in an SPS Tank

[Aquarist007]

for future consideration-----while your alk is falling

what is your pH----did you or are you dosing with a buffer---alot contain boron which can raise your alk levels very high.

[sdoggssf]

Thanks for the imput guys, i really appreciate it.

[Joyt]

Nice thread.

Need some help from expert advise
tank size 120 gal

I'm currently dosing Randy's receipe 1 for my SPS tank
Kh 50ml - 2 hrs once start from 12am (eg. 12am, 2am, 4am ...)
Ca 90ml - 2 hrs once start from 1am (Eg. 1am, 3am, 5am....)
each dosing amount will last 55mins and 5 mins rest before the next one started (about 7drops or so every 20sec estimated)
Total dosing amount at night Kh 350ml ca700ml

Mg 300ml every 3 days once at 7pm

Every night measure at 9.00pm Ca 400-420, kh 8.0-8.4 Mg 1280-1320

i struggled for almost 2 weeks before i manage to get this result due to ionic imbalance

Recently, PH drop significantly after switching all the dosing after lights off. Now (8.0-8.3) before was (8.2-8.5). I'm contemplating to slowly adjust back to 8.1-8.4 by delaying the dosing starting from 4am instead of 12am.

I'm very keen to know
1) Is there any way to measure the highly concentrated dosing solution using our test kit.
2) I don't know why but i need to dose a lot more ca solution than kh - i'm worry. Is it because CA precipitate causing more solution required when dosing?
3) what is the safe dosing amount/qty quantity within an hour ?

Hope someone can share his experience. Thanks

[melev]

Joyt,


To Reef Central

Why are you dosing so frequently? It appears you are dosing every two hours?

It sure sounds like you are dosing more than is necessary for a 120g tank, but when I was dosing, it was with B-Ionic.

[Wonder]

wrong post

[MCsaxmaster]

For measuring the concentration of the solutions you could do a 50 or 100 fold dilution (or whatever dilution you'd like to) and measure the concentrations. Make sure you're as accurate as possible in diluting, otherwise your calculated values will be off.

A possible and perhaps likely reason that the you need to use more of the calcium solution is that the actual calcium concentration is lower than calculated value due to hydration of the calcium chloride. Calcium chloride picks up water very, very easily (used as a dehydrant in some applications because it sucks up water so easily). This means that you may have mixed up a more dilute solution than you intended because much of the mass/volume of the salt was actually just water.

That does seem like a lot of dosing, so I'd be suspicious that a lot of what you're adding is precipitating abiotically. How exactly are you adding these solutions?

cj

[JetCat USA]

Originally posted by MCsaxmaster
........That does seem like a lot of dosing.......

He might have a huge pair of Gigas in there

[Aquarist007]

Originally posted by JetCat USA
He might have a huge pair of Gigas in there

lol I had to look this one up--for other duh"s like myself they are giant clams

http://animaldiversity.ummz.umich.ed...cna_gigas.html

[MCsaxmaster]

"One point twenty-one gigawatts?! One point twenty-one gigawatts!?!"

[Joyt]

Originally posted by MCsaxmaster
For measuring the concentration of the solutions you could do a 50 or 100 fold dilution (or whatever dilution you'd like to) and measure the concentrations. Make sure you're as accurate as possible in diluting, otherwise your calculated values will be off.

A possible and perhaps likely reason that the you need to use more of the calcium solution is that the actual calcium concentration is lower than calculated value due to hydration of the calcium chloride. Calcium chloride picks up water very, very easily (used as a dehydrant in some applications because it sucks up water so easily). This means that you may have mixed up a more dilute solution than you intended because much of the mass/volume of the salt was actually just water.

That does seem like a lot of dosing, so I'd be suspicious that a lot of what you're adding is precipitating abiotically. How exactly are you adding these solutions?

cj

I'm using aquatronica dosing pump, suck from a 8gal storage bottle (seal) and dose directly into my sump at a very high flow area. I did monitor, it is like 1ml/30sec or a min. same happens to kh and ca with an hour apart

Potentially, I have made a mistake when mixing the solution. Anyway, will try your 100 fold dilution method since the suppose solution should be Ca - 47000ppm.

many thanks

[chercm]

guys who to increase mg ?

[Aquarist007]

Originally posted by chercm
guys who to increase mg ?

Do you mean how to increase mg.

Make sure you measure first---it should be at 1300.

I use Kent Tech-m

[chercm]

Originally posted by capn_hylinur
Do you mean how to increase mg.

Make sure you measure first---it should be at 1300.

I use Kent Tech-m

i tried using Kent Tech-M but i cannot get the 1300. does it help by using epsom salt ?

[JB NY]

I use ESV liquid mg

[Aquarist007]

Originally posted by chercm
i tried using Kent Tech-M but i cannot get the 1300. does it help by using epsom salt ?

what are your calcium and magnesium levels? and how are you dosing calcium?

[chercm]

i am using kent marine turbo calcium

[Aquarist007]

Originally posted by chercm
i am using kent marine turbo calcium

good product

its really important to know your calcium, magnesium , alk and pH levels---can you post these?

[Zedar]

Joyt,

why are you dosing so much so fast? 90ml every 2 hrs? thats too much.

I run my dosers 24/7

I dose 11 ml per hour of each.

11ml x 24 hrs = 264 ml per day

Its better to dose slowly all day long then large amount quickly.

I arrived at that value easily. I did a search on RC to find what most people were dosing for my tank size. I started with that figure (9ml per hr I think it was) and fine tuned it from there.

I recently went to dosing Kalk using a reactor to lower my 2 part usage and to raise my pH. Its working beautifully.
Between running a hose to the outside for the skimmer and running Kalk my pH has gone from 77 to 8.1

[Joyt]

Originally posted by Zedar
Joyt,

why are you dosing so much so fast? 90ml every 2 hrs? thats too much.

I run my dosers 24/7

I dose 11 ml per hour of each.

11ml x 24 hrs = 264 ml per day

Its better to dose slowly all day long then large amount quickly.

I arrived at that value easily. I did a search on RC to find what most people were dosing for my tank size. I started with that figure (9ml per hr I think it was) and fine tuned it from there.

I recently went to dosing Kalk using a reactor to lower my 2 part usage and to raise my pH. Its working beautifully.
Between running a hose to the outside for the skimmer and running Kalk my pH has gone from 77 to 8.1

Zedar,

Discover that my Ca solution was too diluted after using cj measuring method. dreaming while mixing the solution . Now, everything is back to normal.

[ahchung]

May I know what is the difference you observed from SPS when magnesium level is at 1450-1500 ppm compared with that of 1300 ppm?

Originally posted by JB NY

Magnesium.
...
I personally like to maintain magnesium levels at 1450-1500 ppm. For me that has worked out best. it allows me to easily maintain my alk and ca levels and my corals seem to do best at this level as well.
...

[JB NY]

I felt I had less problems keeping alk and ca stable. Also I personally felt I had slightly better coloration, YMMV on that part.

[Aquarist007]

Originally posted by JB NY
I felt I had less problems keeping alk and ca stable. Also I personally felt I had slightly better coloration, YMMV on that part.

I think it was posted somewhere that high levels of magnesium carbonate can interfer with coral uptake of carbonates from calcium carbonate. I think it also went on that in very high levels of magnesium the corals can use it but with much less effeciency then they do with calcium carbonate.

[JB NY]

What is considered very high?

[Aquarist007]

Originally posted by JB NY
What is considered very high?

1500ppm or more

the articles/threads are on my laptop--I'll post them tomorrow

[MCsaxmaster]

Originally posted by capn_hylinur
1500ppm or more

the articles/threads are on my laptop--I'll post them tomorrow

Please do as I'm curious. Suffice it to say, things cannot be quite as you described above