Hello all,I’ve got a pretty big problem with diatoms in my tank, it is 71L and has been running for four years now. They cover a lot of the plants, rocks and much of the back glass and filter. They’re not causing an issue to the fish but I would like to get rid of them and find out why they’re so prevalent. The tank has quite a large bio load with almost 100 endlers, 2 honey gouramis and a Siamese Algae Eater so maybe that has something to do with it? Nitrate levels are normally around 40ppm on doing a water change. I’ll be moving most of the fish to a 200L tank shortly so maybe that will help. I have recently restarted fertilising the plants with Tropica Premium after months of no ferts so I suspect that could play a role, I don’t use CO2 either. The lights are on usually for 12 hours a day.What would you guys recommend? Should the diatoms fade when I move most of the fish to the new tank and should I have the lights on for less time per day? I would be grateful for any other advice.Thank you