CA testiing with Salifert test

[chucknsheila]

When testing Ca with a salifert test is it when the liquid in the vial makes a big change and goes from pink/red to purple/violet or as it says in the instructions until blue? I continuously read high CA-450 ppm. I do not add any CA; use plain RODI for top off except when PH gets too low. Then I use kalk water, 1 out of 3 days about. I have done this for about 1 month and still my CA reads about 450. I have done at least 4 water changes of 15% each. Alk stays good and all else is good.
HELP

[Engine 7]

Do you have clams or sps in your tank? What kind of salt do you use? You say you do nont add ca, but adding kalk is adding ca.

Jeff

[chucknsheila]

Thanks for the reply!
I have 1 clam, about 5 frags / small hard corals, frogspawn, about a dozen or so various mushrooms ect. I did not think the kalk would add much CA. Rod from Rod's Reef is advising g me how to correct and I'm doing as told, but the CA wont come down. I know 450 is not that high but I'd like it to be correct. Rod said top-off with just RODI water until CA comes down, and then goes back to kalk for top-off. My PH started to drop after about 3 days and Rod advised to start toping -off again with the kalk un till the PH came back up. I have been doing this for about or just over 1 month. I'm using Coralife scientific grade marine salt. I have checked the cA from my new mix and it actually is a little low??
Any ideas

[Engine 7]

Well, Rod is the man. Sounds like you are doing things correctly. Are you sure you are using the test kit correctly? I use the Slaifert myself and it can be tricky the first few times.

Jeff

[chucknsheila]

i just last week purchased the Salifert test kit. It actually shows my CA lower that my preevious test kit and is easyer to use.
i find that I see a great change in color from pink/red to purple/violet at about 400ppm but to get true blue I'm at about 450ppm.