How can I clean out a very moldy fish tank?

[eemmais]

So I'm getting a used fish tank from my friends sister. The thing is, she didn't do a good job with water changesvand the thing is covered in mold/algae. What should I use to clean it? There's so much that you wouldn't be able to see anything inside the tank if you set it up. I tried hosing it off but there's still some mold that I can't seem to get off with just water.

[chardzard]

is it a glass tank if yes u can scrub it with that green thing u clean pots n pans with some mem may scream at me for telling u to use "bleach" fill up the tank add the bleach normal bleach tho and let it scoak for about 30 mins then scrub it n let it dry for 1day yea it sound crazy i know but if u dout wat i'm saying check wat they treat tap water with n see it in bleach too just lots more of it that all ,

[GoodMorning]

there are scrubbing brushes made for aquariums, i think i got mine a long time ago for under $5. I also agree with charizard, you can try those scotch-brite dishwasing pads, if it doesn't scratch your glass cups, then it shouldn't scratch ur glass aquarium.

[babystarz]

After using bleach, you need to rinse it out really well 15-20 times. Then leave it outside for at least a day in direct sunlight; the light will break down any remaining bleach particles and make them non-toxic.