Unbalanced Ca/Alk usage

[Hexboy]

My tank uses Alk much more quickly that it uses Ca. If I achieve a balanced state (about 410 Ca, and 2.8 Alk), over 3-4 days, the Ca will fall slowly to 400, while the Alk will fall to 2.4.

So I have two questions:

1) What might be causing my tank to use Ca/Alk in an unbalanced way? Is it possible that Ca is being released into the system in some way?

2) Could I add extra Alk to Kalk drip such to compensate for the extra Alk demand? If so, what additive should be added?

(OK..so that is sort of 4 questions...) :wink:

 

[RicardoMiozzo]

Ca++ and Alk have a relation, but it is not so obvious. The animals do not have to consume them in a balanced (equal) condition.
Anyway, your parameters are far from being bad. If you could just keep them as thy are, it's perfect. If it comes necessary to add more alk additive to keep it around 2.2/2.4 Meq/L, it's OK. Calcium is not necessarily needed to be kept over 380/400 ppm Ca++.

 

[Hexboy]

Thanks...maybe I'll shoot for a lower, balanced level. Maybe there is more stability at levels lower than 410/2.8

I've been able to stabilize the Alk by dosing Seachem Reef Builder 1 tsp/l at 12ml/hr.

Ca drops much, much more slowly and I'll just do weekly additions of Ca to bring it back to target.

I've only got one doser and I can't mix the Ca and Alk additives in the same container. Kalk is tempting, but it's Ca/Alk ratio is not appropriate to my needs unless I can add Alk to it.

 

[wade1]

Your input source can also have an impact. I find that calcium reactors provide the best balance by far, then kalkwasser reactors, and then 2-part additives.

 

[RicardoMiozzo]

I'd use kalkwasser, if your need for Ca++ is so low.
Seachem Calcium is a blend of things, and has a lot of calcium, but linked to other chemicals to make it have so much Ca++. Kalkwasser, in the other hand, has several advantages a.k.a. PO4 export from water - and used the right way, improves Alk, also. The good thing is that kalkwasser (calcium hydroxide) is not more than CaOH and water, so you never have other chemical structures other than Ca++ free in the water.

 

[Hexboy]

Unfortunately, I don't have a calcium reactor and don't really have room to add one at this time.

This is the root of the problem. If I dose Kalk to stabilize Alk, my Ca levels climb too high. If I dose Kalk just enough to maintain Ca, my Alk level falls steadily.

 

[RicardoMiozzo]

Try using kalkwasser slowly dripping at night only, in a way you can control the pH raise, that causes the Alk drop if too much CaOh is dosed.

 

[wade1]

Kalk is a good additive, but cannot be used on high evaporation systems alone for that exact reason. It pushes too much Ca into the tank (as well as pushes the pH way up). You will have to work on your own solutions, but one thing that will really help is regular water changes with a quality salt. That goes a long way towards keeping many things in check, including ca and alk levels.

 

[Hexboy]

I don't dose related to evaporation. Evaporation is compensated by a separate system that delivers RO/DI water. In my case, evaporation is not related to Kalk addition.

Ph has not been a problem.

Generally, regular water changes do not cause any significant movement in these parameters. (% of water change is not too large and the replaced water is pretty close the the tank parameters). I would have to a significant amount of water exchange to caused a significant change in the parameters. Besides, I'm going for stability, rather than a weekly adjustment caused by water change or an additive addition.

 

[guara]

I have had the same problem with my CA++ but my ph is around 8,5 I think it is good.....when I try to measure nothing happen....I think it is less then 350....what can I do to raise it?
I have been put it in my aquario by botlle water,I mean by 1 litre everyday...please help me to find the right way to increase my CA.....

 

[wade1]

Regular water changes will help a great deal. Using CaCl2 (calcium chloride) is a sure way to bring it up, but it needs caution! Do it slowly so as not to make the alkalinity crash.

 

[guara]

Thank you Wade for our help....I'll do it

 

[Altaaf]

Hello, hope u can help:

In your opinion, what is the best way to add Kalwasser. slow drip at night/24hrs/your suggestion?

thanks, much appreciated.

cheers

 

[wade1]

IMO, it is significantly better to add kalk in a topoff style where you are adding constantly throughout the day. If you add too much at once, you cause pH spikes as well as risk precipitation of dissolved minerals from the water.

That said, it can help to balance out the increase in CO2 present at night in most reef tanks that depresses the pH slightly (however temporarily).