alk and Ca Question

[Eric JIM]

I am new. I hope you can give me a good suggestions.
I added my DIY Ca reactor in my 200Litre reef tank a few months ago, it works great. I checked the alk. and Ca level one week ago, alk.=17KH, pH=8.17, Ca=65oppm. I think Ca level and alk are both too high, I want to grow some coralline aglea on my live rock, but not success. My lighting is 150w 6500K MH and two 03 blue lights. The lighting should be ok.
Help me! Any suggestion is welcome, and thank you.

 

[randy holmes-farley]

Yes, both the calcium and alkalinty are very high, presumably because the reactor is pumping out much more than you need (assuming that the test kits are correct).

Here's an article on calcium and alkalinity values:

http://www.advancedaquarist.com/issues/nov2002/chem.htm

 

[Eric JIM]

That means I have to stop using Ca reactor untill falling back to 400ppm.
And also high Ca and alk. will hurt the reef. and any effect on the growth of coralline aglea since I want to grow some coralline aglea in my reef tank, but i add the Ca reactor for few months but can't see any different or any growth. Need help.

 

[randy holmes-farley]

Yes, if those numbers are correct, you should stop or slow down the rector and let them fall.

I don't know if the alkalinity or calcium can be so high that it harms coralline growth.

But other things certainly can, including high phosphate. Have you ever measured phosphate?

 

[Eric JIM]

Yes, I checked the conc. of phosphate yesterday. it is about 1ppm0.5-1ppm, is this the problem for stopping the growth of the coraline aglea.

Thank for your kindly reply:>>>>

 

[randy holmes-farley]

If that value is correct, then I expect it is a big problem, yes.

Here's an article on phosphorus:

http://www.advancedaquarist.com/issues/ ... 2/chem.htm

 

[Eric JIM]

Randy,

You are great for answering my Questions and helping me a lot.
Instead of using the PO4 absorber, people like adding PO4-Minus,which is German made. Does it work and have you ever used this chemical in reef tank before.
This is the link for PO4-Minus.
http://www.korallin.com/po4engl.htm

Please advise and thank a lot.


Eric

 

[randy holmes-farley]

I don't know anything about it in particular, but I believe that some these kind of things work by generating a bacterial bloom that consumes phosphate as it grows. That isn't necessarily bad, but I wouldn't probably go that route in my tank.

I do find this claim rather odd:

Best to be used with the Korallin Trace Elements to maintain a healthy kH.

I'm not sure what trace elements or phosphate have to do with KH.

 

[Eric JIM]

Thank you for your kindly reply!

What do you usually use to absorb PO4, is Kent's PO4 sponge a good choice. From the web site, they say that this absorber can be regenerated in high temp. any limitation? how many time that can be regenerated?
The chemical equation od this absorber is Al2O3, right?

Thank you.

Eric

 

[randy holmes-farley]

I export phosphorus with a skimmer and by growing macroalgae. The article linked below describes these methods.

I would not try to reuse any phosphate absorbing compound once it is saturated with phosphate.