live rock leaching phosphate

[pan_Oz]

Hello everyone!



I'm currently curing some live rock for my new set up. Actualy I'm cycling both live rock and dry rock in different buckets. My plan is to use my 4.5kg dry rock (caribsea life rock) for my display tank and the 5kg live rock in the sump.
I'm on the second week of curing live rock changing the water every 4-5 days and the rock stil leaching phosphate. Once I brought it home the measurament was 0.6ppm and now its 0.43ppm using hanna ulr.
I have done some amonia tests and it is always under 0.15
My nitrates are 20ppm and I don't test for nitrites
Is it normal for LR to leach that much phosphates? Do I hane to use GFO or lanthanum chloride to reduce them?

this is my live rock .. no coralline algae on it except one piece of rock...


and the caribsea life rock that I'm planning to use in my display tank..

 

[basement reefer]

I would imagine as long as there is die-off happening in the bucket you are going to have some measurable phosphate.
If that bucket was an aquarium, I would suspect it would take more then 2 weeks for that rock to stop rotting and for the cycle to happen.