What should i use to clean a used fish aquarium?

I purchased two used aquariums. I want to clean them out before getting them set up, but I'm not sure what I should use. I'm planning to use the aquariums for fresh water fish.

soap...disinfectant...spondge...water...thats it...

Is there lime on the tanks? You can buy special cleaning solutions from a pet store that are safe for fish. NEVER use soap in an aquarium

To remove old lime scale on the glass, use a straight edge razor blade. Just be careful that you don't cut yourself. A salt water solution will disinfect the tank for bacteria, mold, fungus or any parasites that might still be around. Rinse well and you should be set. If you got gravel with the tank, rinse it several times in a clean bucket until the water runs clear. This will preserve some of the good nitrifying bacterial so your tank will cycle faster.

I have heard that you can use white vinegar and water to remove the white film, be sure to rinse it out really good. Thats what the told me at pet smart.

Get some grubby clothes on that you don't mind getting ruined, because bleach is your best bet.So grab a bottle of bleach, some rubber gloves, and a new sponge...and wait for a sunny day.On that sunny day, take the tanks outside and pour about a half inch of bleach into each tank (if the fumes are too strong for you, wear a mask or pour in some water) but you want it to be as strong as possible. Wearing the gloves, soak the sponge in the bleach and rub all over the tank, especially where the glass and edging meet. Dip the sponge frequently - there's no point in dry-rubbing it on the tank walls.Let sit for 10 minutes (now it's okay if it dries a bit). This will allow disinfection.After 10 minutes, rinse off with the hose. This is a good time to check for leaks, so I usually just fill the whole thing, bleach and all, to the top with hose water and check for leaks. If all is well, then I just let it overflow till I can't smell the bleach anymore. This will require you at one point to CAREFULLY bail out the water (or if your tank is small enough, tip all the water out) and give it a good sniff. Any traces of bleach or chlorine should be given another good hose down.Once completely rinsed and drained, leave the tanks out in the sun to dry. The dose of UV radiation will kill anything left behind, but usually the bleach itself does the job.I did this with my 30g tank (previously used with leftover tank water from 50 YEARS ago!), and had no problems.

Fresh water and a scrubbing brush/ sponge/ nylon scrubbieYou can use vinegar, salt or PLAIN diluted bleach, as long as you rinse well afterwards,Never use soap or detergent, it toxic to fish and hard to get rid of all the residue.The tanks dont have to be sterilised, they are going to grow more bacteria and algae as soon as you fill them up anyway. Just get them looking clean and your fish will be fine.Ian

You can use bleach to clean them.You just need to be VERY careful with it.Rinse the tank well, fill it up with a bleach solution [19 parts water to one part bleach] and let it soak for a couple hours. Dump that water, rinse it, fill it with fresh water and twice the normal amount of dechlorinator and let soak for 24 hours. Dump, rinse and use.I've done it on my tanks with no adverse side effects.