Jesus Murphy, How did it get so high!
 

Tested the calcium for the first time today, only usually dose like once a week, but the calcium readout was a whopping 620mg/l. In shock I stumbled back into a shelf. Is that safe?!?! I didnt really stumble back but you get my concern,

I'd question that result. Retest, or try another kit. at that level, I would expect it to precipitate from solution.

what test kit are you using?

API Calcium test kit.

check your Alk and Mg too.
IF your alk or Mg is not in proper proportions, its probably not using the calcium up properly hence the higher readings.

I don't know who Jesus Murphy is but he sure put a lot of calcium in your tank.. Although I too would question that result. It would be worth while to get a second opinion at least. Borrow someone's test kit (of a different brand perhaps), and test to verify the result.

API calcium test kit known to be inaccurate, usually reads high. I will suggestion you testing it with a different test kit (elos, hanna, or salifert), or bring your water to your LFS and ask them to test it for you, using one of higher quality test kits.

if your dosing calcium im assumiong you have alot of high demanding corals or at least a full tank?? its def not a good idea to dose anything without testing for it reguarily:p

I would say you have a false reading. You would think that if it was that high you would have calcium precipitation. this is just my thoughts about it! You could also take a water sample to your local fish store and ask them to test it for you or ask a friend to come over with there kit and retest it!

Lol our lfs uses the API so I wouldn't be better off :mrgreen:

Hmmm, ive retested and my reading is the same. I thought my maxima clam would be suckin it out

A single clam isn't going to move the Ca level at all. And if it's that high for real, the chemistry might be so messed up that nothing can use it anyway. But I'm pretty certain it's not really that high.