Originally Posted by Autumnsky
Looks like some algae.
How long has the tank been set up?
How long are you leaving the lights on for?
How is your circulation and water flow in the tank?
In my signature line below is a great article for beginning fishkeeping. Definitely worth it to have as a resource, especially to understanding the nitrification cycle.
Tank has been set up for about 7 weeks now, I did the fishless cycle as the advice from my local fish store and took water sample in for tests weekly. Water parameters are all okay I believe PH:7 Ammonia:0 Nitrite:0 and Nitrate is between 30-40.
Lights are on for 6-8 hours depending on my work schedule.
I have recently added a small airstone to help with water flow.
How would I go about fixing if it is algae? I have a small bristlenose pleco in the tank as well as some harlequin rasbora and a dwarf gourami