Dirty 20 gallon

[reflex1]

I purchased a used 20 gal this past spring and am just now attempting to clean it but having problems with "scum" and dried algae - have tried diluted and straight vinegar to no avail - even used a razor blade to scrape it - all to no avail - any more ideas before I scrap it and buy another "cleaner" tank? Thanks.

 

[mattrox]

Fill it with hot tap water, let it sit so the scum softens.... then razor blade....

 

[HN1]

5% bleach solution. Let it sit, rinse copiously.

 

[RaptorBro]

my 20gL was like that i used a sponge with the green scrubb side and hot water worked out good.

 

[reflex1]

Thanks for all the suggestions - will certainly try them - what about Simple Green?