calcium carbonate

[cgarr017]

i posted a couple days ago about how to raise calcium without raising alk and was referred to bulkreefsupply calcium carbonate. i ordered some and used their dosage calculator to calculate the amount to use to increase calcium from 320 to 350 just so that i don't shock any livestock by raising too fast. to dosage for raising total water volume-75g(underestimated) 30ppm was 5.2 tsp. i did that and it rose it from 320ppm to 420ppm. am i doing something wrong with this dosage calculator? could something have gone wrong by raising the level this high this fast?

[bertoni]

I think you mean calcium chloride? Is this anhydrous? I don't know what that vendor actually ships.

100 ppm per day seems to be safe for the animals. I wouldn't worry to much. The calculator is usually fairly accurate, but it requires a guess as to the actual water volume. I get about 8 tsp or so to raise the calcium 100 ppm, assuming 40 g of water in the system and anhydrous calcium chloride.

Also, which calcium test kit is being used, and what is its resolution?

[cgarr017]

calcium chloride yea. i am testing with api test kits and the water volume is actually more than 75 which i calculated with. i have 75g tank with 75lb rock and 20g sump

[bertoni]

Well, the calculator needs to know the amount of water in the tank, and usually, the live rock and sand consume a lot of space. I wouldn't worry much, but I'd use a smaller number for the water column size in the future.

[cgarr017]

so since yesterday when i tested and it was at 420, today it is at 360 and the water is slightly cloudy. however alk has remained the same at 10 and mag is the same at 1420...

[bertoni]

So what's been dosed into the tank, if anything, since the measurements yesterday.

[cgarr017]

nothing since that one dose of calcium chloride

[bertoni]

Hmm, I think I'd continuing testing for a few days and see what the trend line is like.

How cloudy is the tank? Can you get a second opinion on the test kits easily?

[cgarr017]

i dunno just slightly cloudy, still enough light penetration for my clam to be all the way open. i might be able to use a friends calcium test but my api tests have been reliable in the past so im sure its reading correctly. it does seem to be getting cloudier just very slowly. should i wait it out and keep testing or do a water change

[akindbro4u]

just my two cents, but i would test the Alk again. It sounds to me like calcium precipitation. that would explain the drop in calcium. What are your other parramiters. Mostly PH and salinity.

[bertoni]

The cloud likely will settle on its own, but something's strange somewhere with those parameters.

[cgarr017]

alk-9.5, sal- 1.0245, ph-8.4