Salifert DKH reading

[axe_man16]

What causes this to happen? You are right my cal is around 550. It usually is at 450 or 425 my SG is at 1.026 just as it always is.

[phi delt reefer]

no clue to be honest but thats how the two seem to be related.

if your tank is new your system could be heavily using alk during the startup - i found that was the case with mine. I just doesed alk for months then finally my calcium started depleting below 400

[axe_man16]

Tank is over 2 years. And i did a water change on Monday my calcium was 450 i tested the new water it was 350 so I added 3 capfulls of my calcium additive to get it to 450, did another test and it was fine. So I test the tank now and it is 550 for the calcium. A bit baffled

[phi delt reefer]

only thing i could say is your calcium test must have been off... even then three capfuls of calcium in a water change isnt going to bump your calcium that much unless its like a 5 gallon nano

[axe_man16]

It is very weird. My tank is 60 gallons with a 15g fuge, and a 30g sump. So a 5gallon water change shouldnt do that. Going to retest once more, but have gotten three tests all the same

[jostafew]

Not saying that this IS your problem, but I'm facing a similar issue and I'm pretty confident it was due to a bad batch of salt... Took me a long time to discover it and unfortunatly things got pretty bad. Mag and Calc were WAY high, Alk was low. I should have known better when the salt had an unusual texture and it took more than my usual 2.5 cups / 5gal to reach the desired SG.

The moral of my story is measure your freshly mixed water and make sure it isn't going into the tank already messed up.

[axe_man16]

The weird thing is that i did test the water before i did the change as I havnt checked it in a while. All was good then checked it next day and the parms were out of wack.