p04 problem

[LIM CHYE HUAT]

i did a 60 % water change (20 % each time every 2 days) with coralife salt to reduce n03 from over 100ppm to 20ppm, but the thing is my po4 doesnt seem to lower as well measuring at 1.0mg/l

s.g= 1.0235 at 26 degree c

ph = 8.0 to 8.1

kh = 9-10dkh

po4 = 1.0mg/l

no3 = 20mg/l

ca = 500ppm

and also the ph is a bit low 8.0 to 8.1 measured after on the mh for 3 to 4 hrs.

is the ca too high also how to bring in down then ?

any help ?

[lightningstrike]

is ur water change done with RO/DI water?

[LIM CHYE HUAT]

is ur water change done with RO/DI water?

no using tapwater , but i ever test for p04 and it measures about 0.1mg/l.

[Reefbum]

PO4 can come from these sources and will accumulate over time if not reduced.

1)Tapwater that is not conditioned.(includes intial set-up)

2)Fish food(some contain high levels of po4)

3)Sand bed( try using real coral sand or argonite)

You can try using rowaphos if these sources are not contributing to the problem.

[lightningstrike]

Good Article to read with regards to PO4 problems.

http://www.advancedaquarist.com/issues/sept2002/chem.htm