gunk in Fresh Water Tank - 2000 25C Safari

[WA_Safari]

We did not use our trailer last year, and I must not have winterized properly (probably more than once in the last 17 years). I've been trying to get rid of small floaters. Sanitized with bleach and have drained the tank twice. today I filled it to the top and gave it a slight over pressurization with hose, so water streamed back out the fill port. The water looks like in the picture.

I'm thinking I need to have the tank replaced, unless there is help on cleaning it out.

[AWCHIEF]

Continue to clean, sanatize and rinse. Hopefully it will get all the gunk out.

[YippieKiYa]

Fill it halfway, take it for a drive, drain it out the bottom and rinse another time or two?