New tank PO4 questions

[zonda]

Hi there, I just set up a new 50g tank cycled a month ago, afterwards I put some corals week by week, all the reading was normal, all of the sudden the PO4 went up from 0.09 to 0.34 last night no idea what caused, other reading looks fine PH was 9.4 NO3 was about 5ppm, I do a 20% water change every week. How long can my corals survive under a high level of PO4? How soon do I have to take some actions on it? Thanks

 

[SPR1968]

I would just double check the phosphate and ph readings to make sure it’s not test error, but you may need something to remove phosphate from the system if the water changes can’t keep up with it.

I use rowaphos in both my systems

I would also check the quality of the water your using for water changes, make sure the clean water is 0 TDS RODI water, otherwise you could be introducing phosphate with the fresh saltwater

The tank looks good though so don’t panic just yet.