Ok so i have 22gallon approx. that is old 1.5 months, for last three weeks my water parameters are stable ammonia 0, nitrite 0, nitrate 18. I have a lot of plants but for substrate i have just some white/grey gravel that doesn't have any nutrients. Plus now i get that white substrate can't look clean whatever i do. So plan is to buy jbl volcano powder (macroelements) and flourite black or black sand (i have apistogramma so maybe sand) beacuse i have established tank and i dont want to put soil as that would cause ammonia spike and i don't have time to do few water changes daily for week or two. Then i would buy few buckets and plastic container, move all fish in container plug there heater, two filters that i have inside of tank now. Move all hard scape, move all plants out. Dry out water i would try to save at least 50-70% of tank water. Remove old gravel, put down 100g of jbl volcano powder, on top of that pre cleand flourite black or black sand. Put some foil over it (aluminum, plastic etc.) and start putting some old water in, lets say until 1/3 then put back hard scape and plants in, put rest of aquarium water and fresh treated water inside of tank, then i would put bigger filter juwel bioflow one in tank with aquarium polish media as pre filter(and i would leave for now in container pat mini sponge filter). I would add some ffm, wait 2-3 hours and then add back extra water and fishes in tank. I would put after that dose of voogle plus maybe i would put easy start bottled bacteria (i have one or two doses) in substrate before i put it in tank. Dose this sound like good plan? Any other suggestions?