phosphates

[Colin Gilboy]

so, i have had this problem for about a week, this tank has been set up for years and recently its gone thru a lot. had velvet two months ago, then skimmer broke, now phosphates. not a single fish has seen the tank in two months. i’ve done many water changes, upgraded to a new better skimmer, i even blacked out the tank to get my algae bloom down and it worked. Of course tho the phosphates are still there. i’ve done many water changes, and even have 4 packs of phosgaurd (60 gal treatment per bag) and still no change in any level. any advice?

 

[BadFish619]

Have you tested the water you use to mix salt for phosphates? Might just be taking them out and putting them right back in

 

[SPR1968]

If you have had live rock in the tank the phosphate could be held up in the rockwork and it still leaching out?

Assuming your using 0 TDS RODI water for your new saltwater so your not reintroducing nutrients from that

If it’s the rockwork I would just keep changing the GFO until it clears it all out so it may require regular changes.

 

[PatW]

I agree, once a system has high phosphates for some time, the rocks absorb it. Once phosphates start to get removed, the phosphates leech out of the rock. It can take time to get it out. Something to watch for is once you have lowered the phosphates is over shooting and having no phosphates and starving your system.