2500 gallon poly tank w/MOLD

[OneLegJohn]

Looking for some advice. I found a used 2500 gallon poly tank. It has been used for water only. However, it has some mold in it. Is this normal for poly tanks? Tractor Supply style. Now, being a chemist, I have no shortage of ways to kill, clean, and sterilize this tank. I'm just curious as to if this tank is worth my time at $500.

[farmall h]

Absolutely! I'll take it off your hands for free! I cleaned a 300 gal. poly tank that I used to truck water with and left it out side with the cap off. I used a milkroom powdered cleanser with about a foot of hot water. Brush it around then blasted it with a pressure washer. Clean as new. Oh, rinsed it with bleach and water as a final step. If the access hole is large enough it is easy to wand the mold off.

[OneLegJohn]

I typically use hot water through a power washer to clean my tanks. You are right, it cleans plastic to like-new condition.

[maplecrest]

do not use bleach if you have an r/o