Background: I have a 37 gallon tank that is 22" high with the lighting that came with my tank, which is maybe a 12" long LED (45 watts). I change the water typically 25% twice per week. My lights are on about 10 hours per day. I planted some small plants maybe 5 weeks ago (all low light plants). Issue: I suspected that my light wasn't strong enough but I wanted to see what would happen. My Anubis, cryptocoryne becketti and staurogyne repens are doing well with no yellowing. My helathium quadricostatus has some bottom leaves melting, has some small holes but it is growing. My java fern has brown spots all over it. I'm assuming this is a lack of light problem, but could it be a deficiency issue instead? I have no CO2 and I just ran out of Flourish. I had bought a replace the bottle but realized I got Flourish Excel instead. I do have a new light on order. Edit: I'm also using root tabs. The Java fern was free floating but I stuck it in A pail and put it outside for the day to get some light.