View Full Version : low ca

01/14/2008, 01:20 AM
i have my nano cube at 200 ppm of ca at the present and added ESV 2part ca buffer system my ph has been at 8.2-8.4 so the dh should be good but my ca is running low and I am planning to get it balanced and then go on and add more animals till the tank has settled in does any one know if i can add more ca without hurting the livestock in the tank? it is a 24 gal nanocube

01/14/2008, 04:39 PM
It's generally safe to dose up to 100 ppm per day. This calculator will help with a dose:


That calcium level is very low. Are pH buffers being dosed into it? I'm worried that the test kit might be wrong. Have you tested some freshly-mixed saltwater? That'd be a good sanity test.

01/14/2008, 08:10 PM
I would test your water source first. That small of a tank, do a water change.

01/14/2008, 11:09 PM
I'd say either your test kit is bad or you are mixing your salt water way too lean.

Even the lowest salt mix I know has about 350ppm calcium.

01/15/2008, 12:32 AM
first i am using real ocean so that should have been at 400ppm
and I did test it calcium 400ppm, salinty 1.021, ph8.3
test results tonite are: calcium 300ppm, ph 8.3 salinity 1.021

01/15/2008, 12:37 AM
What is "real ocean" and what makes you think it should be 400 ppm ?

01/15/2008, 08:14 AM
You need to first increase salinity to 1.026 or so. BTW at 1.021 sg you would get 280 ppm Ca if you are using Instant Ocean according to Billy's latest salt review. Salt Mixes (http://reefcentral.com/forums/showthread.php?s=&threadid=1287118)
Check Mg if you have a kit.

01/16/2008, 10:57 AM
real ocean is sea water from the sea that has been cured I get it at my lfs no mixing of an artifical salt mixes my salinity is 1.021 -1.022 at this time

Randy Holmes-Farley
01/16/2008, 11:20 AM
Real ocean water at an actual specific gravity of 1.021 will have a calcium level around 334 ppm. That said, I would not maintain a reef aquarium at either that salinity or at that calcium level. :)