Can anyone please tell me what kind of deficiency this looks like? I have 2 anubias and 2 amazon swords in a 75 gallon tank. 6 Discus, a school of cardinals, and a pleco that poops like no other. I change about 40% water daily. I keep lights on 6 hours a day and dose Seachem Flourish once a week currently. Thanks in advance!