I don't know how well you can tell by the picture, but I've had an issue with getting my aquarium clean for weeks now and it seems to be getting worse.
My aquarium has no fish; it's a 10 gallon aquarium currently going through the cycling process.
Everything in my aquarium is covered in "dirt," this brown, powdery substance. Every time I remove it through water changes or by scrubbing off the ornaments (sometimes by taking it out and rinsing it, as well) the "dirt" that's in the water column settles back down onto all of the leaves and the branch and everything else within an hour. The water is also extremely foggy, even though I do major water changes every few days (35-40%, sometimes more). I've also done multiple gravel-vacuums.There are detritus worms floating all throughout the tank now, as well.
I think the reason for all of this is because I initially tried doing a fishless cycle with FISH FLAKES and it made an ABSOLUTE mess! I had "cotton candy" all over my tank and the smell got bad, so I removed it all and gravel vacuumed up as much as I could. Still, I could see pieces laying around, turning black, so I feel like the "dirt" is the decomposed fish flakes. I have a mix of Aqueon and Fluval shrimp & plant substrate, but I feel like it shouldn't have caused me this much of a long-lasting problem.
I don't have any fish in yet, I haven't added any food since then (switched to a liquid ammonia), and the ammonia levels are elevated, yet my tank is thriving with life... ramshorn, trumpet, and bladder snails... nematodes... detritus worms... amphipods... some other, tiny (almost microscopic) creatures... it seems the fish flake leftovers are keeping them well supported? Help!