cheato

[Aquaria]

So i added a 60w 6400k bulb (clip on lamp style) and cheato and did a w/c. I had a cyanide prob before but it was almost all gone and now its growing on all the algae is this a sign of dieoff? Last time I did vsv dosing it just turned white and disappeared. Did I add to much cheato?

[MarkoD]

When you start getting black detritus under the cheato, it means it's dying