I have a 20 gallon long that has A LOT of algea, I'm not talking a little here and there, but covering literally every surface in the aquarium. I have 4 nerite snails, 4 ADF’s, and a betta. I have finnex 30” lighting which is 18 watts. There is so much algea, I usually turn it on at around 8 am and off around 8pm, is that too long? Any advice would help, thanks in advance.