Literally as long as it took to vacuum my floor after I scrubbed my tubs/trays.How long did you have to filter the water for ?
I set up my sock in sump and vacuum/siphon water from top down through sock back into sump.
Im about to clean my new tank for first time this week. I'm going to stick my overflows in socks while I clean my glass thoroughly. Let that circulate until it clears and then siphon out everything I can possibly get from floors and nooks and crannies.
If you and @James_O have nutrients in the water. Its all about removal of the nasties. Everyday with the sock if you have to. I was lol. Eventually nasties will subside and go away. Coraline will take place of nasties.