Cal and Alk dosing?

[Clownfish25]

I have just added a clam to my tank , he has been in for 2 full days. I have noticed since his addition that my calcium has dropped 20ppm each day . Yesterday evening my test result was 380ppm. My tank had been pretty stable at 420 ppm. I want to start dosing a two part solution to the tank. In your experiences what are pros and cons and things to look out for. Also how does dosing effect the fish in the tank. How did you start dosing?

 

[ccCapt]

There is no way 1 clam will use up that much calcium in a day. You only see drops that large in tank full of SPS corals. My guess is testing error. What brand test kit are you using? Some only measure in increments of 10 ppm, so what you look at as being 420, may actually be 410 and likewise what you see as 400 may really be 410. Some hobby grade test kits are not very accurate.
Did you also test alk? The consumption of calcium and alkalinty is linear. For every 18 ppm of calcium used, 2.7 dKH of alk is used. So if your calcium dropped 40 ppm, your alk would have dropped about 5.5 dKH. So if your alk was 10 dKH, it should now be 4.5 dKH.

 

[Clownfish25]

There is no way 1 clam will use up that much calcium in a day. You only see drops that large in tank full of SPS corals. My guess is testing error. What brand test kit are you using? Some only measure in increments of 10 ppm, so what you look at as being 420, may actually be 410 and likewise what you see as 400 may really be 410. Some hobby grade test kits are not very accurate.
Did you also test alk? The consumption of calcium and alkalinty is linear. For every 18 ppm of calcium used, 2.7 dKH of alk is used. So if your calcium dropped 40 ppm, your alk would have dropped about 5.5 dKH. So if your alk was 10 dKH, it should now be 4.5 dKH.

I have 4 acropora frags as well . It could be testing error. I have an API calcium and dkh test kit. I have been testing consistently around 440 and 420 yesterday I noticed calcium at 380 and I introduced the clam on Monday. The alk was at 11 and it rose to 13 the day I tested 380 cal. I know it may not be the most accurate I just haven't purchased the salifert kit yet. When you started dosing your tAnk did you start off very small doses like 5ml a day ?? Need some ideas on how to keep it as stable as possible.

 

[Clownfish25]

There is no way 1 clam will use up that much calcium in a day. You only see drops that large in tank full of SPS corals. My guess is testing error. What brand test kit are you using? Some only measure in increments of 10 ppm, so what you look at as being 420, may actually be 410 and likewise what you see as 400 may really be 410. Some hobby grade test kits are not very accurate.
Did you also test alk? The consumption of calcium and alkalinty is linear. For every 18 ppm of calcium used, 2.7 dKH of alk is used. So if your calcium dropped 40 ppm, your alk would have dropped about 5.5 dKH. So if your alk was 10 dKH, it should now be 4.5 dKH.

I do have a medium size red monti as well

 

[Liberty]

If it the 75gl I'd start with 5 mil of each for two days and test. Adjust the amount, test agin in a day or two
Right now I have two dosing pumps. Alik at 68 mil cal 70 mil. Small doses all day, auto. and don't forget the magnesium.
I test weekly with Hanna for all and cal red sea for magnesium

 

[Clownfish25]

If it the 75gl I'd start with 5 mil of each for two days and test. Adjust the amount, test agin in a day or two
Right now I have two dosing pumps. Alik at 68 mil cal 70 mil. Small doses all day, auto. and don't forget the magnesium.
I test weekly with Hanna for all and cal red sea for magnesium

Thank you for the advice, yes it's for the 75g . this gives me an idea of how to start dosing because I don't want to do it wrong and kill everything in the tank. Ill start with 5ml . Now do you dose cal through out the day and alk at night, or both at the same time.

 

[Liberty]

Alk first, wait 10 min then cal. Check your mag first. Tank needs it but does not use it that fast
BRS has a vid on u tub.