Calcium level

[Deb2]

My reef tank has been up and running for about 3 months and I have added some corals, mostly soft. I am having a hard time keeping the calcium level up. I have been dripping kalkwasser into the tank and I have been replacing evaporated volume. Any suggestions?

[Satchmo]

What numbers are you getting specifically and what test kit are you using? Post your calcium readings. Also tell us what your alkalinity levels are. While you're at it, a little more about your system would be helpful. Size? Substrate? Regular water changes?

[Deb2]

Alkalinity is 300 ppm, Ca++ is running between 200 and 250 ppm even after addition of kalkwasser. I also added seachem reef complete. The test kit is red sea calcium.
System is a 150 gallon acrylic tank with a 30 gallon sump. there is about 150 lbs. of live roch and a 4 inch DSB (live sand). Lighting is 2 400 watt metal hallides and 2 VHO actinic strips. I do a 20 to 30% water change every 2 weeks. I also use a protein skimmer.

[Satchmo]

Thanks Deb. Double check your alk test kit. Alkalinity is not measure in ppm, it's measured in dKH or meq/L. Repost the corrected readings when you can.

This is important beacuse your alkalinity levels will directly affect the calcium levels you'll be able to maintain.

[BrianH]

Also please state how much kalk your adding to your top off water. i.e. how tany teaspoons per gallon.

Brian

[Deb2]

I read my test kit right is measures in ppm. I also used another test and it reads 13 dKH, which converts to 235 ppm. From what I read dKH is not a good way to determine alkalinity of seawater because it only measures CO3-- and HCO3- and alkalinity includes more ions. Also that mEq is the best way to measure. I don't have a kit to measure in mEq (by the way I am not trying to be a smart ###, just explaining why I used what I did so I don't look like I pulled a value out of a hat). Now that i look at dKH that is very high. What could be the problem. All fish and inverts are looking good.
2 tsp of kalk per gallon of water.

[BrianH]

IMHO you are going to have to add a calcium booster along with the kalk to raise your calcium levels. When you get them where you want, back off the calcium booster and use the kalk mix to maintain the levels. BTW, your alkalinity will most likely get lower as the calcium rises.
Brian

[Deb2]

Do you mean such as kent calcium supplement? If so I tried that one. Which one works the best?

[Soccer]

From what I've read what your gonna want to do is use a calcium supplement to get your calcium up to where you want it. Then when its there you start dripping your kalkwrasser like your doing now, then you lay of the calcium supplements and the kalk should keep calcium where you want it.

[BrianH]

I've never had a really low calcium problem so I don't have any personal experience. I just adjusted my dosages of B-Ionic to raise the calcium. I've heard kent's turbo calcium recommended on other boards.
Brian