Please help me ,what is???

[Andreaitaly]

I dont know how to destroy that ...no3 0 po4 0 with photometer ca450 mg1180 kh7,5
Light T5 plus One led strip Easy led

 

[Impala67]

I dont know how to destroy that ...no3 0 po4 0 with photometer ca450 mg1180 kh7,5
Light T5 plus One led strip Easy led

If you can take your rock out that has it (no livestock) and spray it with some hydrogen peroxide and then scrub it with a toothbrush do this every day until it goes away. Make sure you wash the rocks off after with rodi water!!