Using 55 Gallon Drums to Prepare Replacement Water?

[Aquariust]

Hi everyone!

My husband brought home 2 new 55 gallon plastic drums (one is closed with siphon pump and one is open-style with lid and siphon pump). He thought they could help me with water changes (all freshwater tanks). It seems to make sense to treat all the water and let it get to the desired temperature in the drum(s) versus me working with multiple 5 gallon buckets. I would appreciate any input or experience on preparing and storing replacement water.

1. Should I aerate the water within the 55 gallon drum? If so, standard pump and airline?

2. Should I and/or is it ok to keep heater in the drum of prepared water?

3. How long will water stored in the drum be ok in there?

4. Should I attempt to keep some filter media or substrate from cycled tank (in mesh bag) in with the replacement water?

5. It seems like a good idea to keep these drums filled with "ready to use" water, but is it really a good idea or are there potential problems etc?

Any experience, advice, etc will be greatly appreciated.

Thanks guys.