Hello all, I have a 14g cube with some ludwgia super reds, rotala indica's, temple, and a couple of others I can't remember. The tank has been going now for 5 months, and it was planted from the beginning. This is the light that I have, it was set to be on for 10 hours. https://www.amazon.com/gp/product/B08SBPVXCW/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&th=1
For a while I could not keep my ludwigias from shedding their leaves and only keeping the very top leaves. So I thought added flourish tabs would be a good idea, and those were added on Sep 11. Then me being inpatient and crazy about the hobby, I bought the Coop's all in one fert and started dosing that on Oct 2nd, and then once more on the 9th. I had to fly out for a funeral on the 9th and didnt return until the 16th. When I got back home, I saw my plants had this black algae on them. I have since turned my light down to 8 hours a day starting at 10am.
Is this too much nutrients or too much light? If I buy a brighter light will I need to begin re-dosing with the fertilizer?