Nitrates are high

[jetajockey]

Flourish comp has a minimal amount of nitrates in it so it could be that your nitrate level is being produced by the fish alone. Have you tested your tap water? If it has nitrates in it also then you may want to swing your tolerances up a little.

Is the tank heavily stocked?

 

[xfactor6699]

Yeah its pretty stocked and the tap is only 10ppm