I’m hoping someone can help me, I'm a novice. Please look at the attached images. I thought at first this was diatoms, but my understanding is that diatoms are slimy and easily rubbed off. What I have here is very tough to remove, even on glass I have to use a razor blade scraper and work at it. You can see the build up around the filter/pump housing. The water parameters seem pretty normal, pH around 6.7, nitrates around 50ppm, marginal nitrite and ammonia. Water changed 30% weekly.
Any thoughts and advice advice on this would be really appreciated.
What is your tap water level of nitrates? Try to ensure that your nitrate level is no more than 20ppm above whatever your tap water nitrate level is, and definitely get ammonia and nitrite down to 0 for each - extra or more frequent water changes ought to help achieve that.
Thanks very much for your reply and suggestions. The nitrate is down to less than 20ppm, the tap water appears to be zero on my liquid test kit.
The growth just doesn't rub off, it's very firmly attached to both vegetation and plastic/glass surfaces. It's not at all slimy, it's quite hairy/feathery. I'm considering pruning the plants quite severely to get rid of the affected growth. I'll certainly try reducing the light.
Mine certainly overtakes the vegetation - I've lost many plants to it in the past. Aquascapers would be horrified but I do take my plants out weekly and give them a brush/swipe with a fishkeeping-specific toothbrush to keep this at bay and prevent it consuming the plants (but do often damage the plants by doing so). The situation seems to have improved a little due to reducing the lighting schedule.
Mine is nowhere near as severe as you describe/show. I don't have any on my tank glass or filter - possibly because I have some nerite snails. Snails and shrimp might be an option for you, as well as keeping your nitrates down at 20ppm. Something to remove phosphates and/or silicates might help; in my own case, I know I have high phosphate levels - tank and tapwater - and put in some phosphate pad but am not noticing any difference so far, likely because any phosphate removal gets replenished by the new source of phosphate at a water change.