calcium help please

The first month and a half i had my tank i was checking calcium and alk and both were good(440/10). This whole time i thought adding water to my tank weekly to makeup for evap was a water change. And this brought along a whole lot of problems so i started doing water changes. Now im doing 15g water changes once a week and my calcium is slowly decresing from 440 to 360 which it is now. So tomarow im gunna run out and buy a calcium buffer, but how long does that take to increase it? cause my brain coral isnt doing to well. lol you cant stop mushroom corals though, they just keep growing. Also when im checking my levels the calcium vial turns purple at 18 drops and ill keep it on my desk and then by the time im done measuring alk the purple fades to pink. That mean im not giving it time to settle or im not supposed to wait that long lol

 

Well it could be a sign that you're tank is having a higher demand for calcium. New coraline growing and a brain can put a dent in it. The main thing you need to remember is to raise it back up slowly. You don't want to add too much too fast or you get calcium precipitation (calcium flakes in the water like snow) to occur.

 

I dont think this is a MAJOR problem (over time it would prohibit the growth of corals - but...) If you have your salt mix and are really worried, do a REAL water change.. Mix up some salt (most quality salts include some calcium) and do a proper water change.

When you add your calcium suppliment to the tank the calcium will go up almost right away (once the cloudyness goes away). I use purple up and part a/b. Check the rest of your water chem its probably somethinge else hurting your coral. How long have you had your tank my friend?

 

had the tank for 4 months, with livestock about 3. yeah tomaro im gunna pick up all my test kits cause ive been checking only ammonia/nitrite/calcium/alk. What else do you suggest i check? and yeah when i get it ill bring it up slow

 

well magnesium plays a big role in calcium levels so test for that. Make sure to test for PH as well.


A general rule is never supplement your tank with anything that you don't test for.

 

Just to expand on Slocal's comments about magnesium playing a big role
as does specific gravity

there are only so many Ions a given body of water can dissolve and the higher the SG , the more dissolved Ions that are present/ can be maintained

the ratio of Magnesium to Calcium is just over 3 to 1 so unless you have a mag level over 1320, then you are not going to be able to maintain a calc level of close to 440

and in fact anything you do in the absence of the required mag level will counter act against other parameters

if you try and increase your DHK by 1 , then if saturation point due to magnesium level has been reached, your calc will drop by 20ppm
so if you then try and increase your calc by 20ppm, your DKH will drop again to compensate

and you get the snow effect, precipitation of these Ions that the water cannot absorb.

so the key is - with a SG of 1.025 - 1.026 - aim to test and then slowly increase your mag level to your target figure and once you have done that, you can then fine tune the balancing act with the calc and DKH levels

Steve