most portable aerators are usually designed to aerate 6g IMO
Frank Castle
I guess the rating is either "give-or-take" or I just got a decent quality one, idk......it easily does 10g+ for 8-12 hours, depending on battery type/quality
Only way to control ammonia would be to connect it to a cycled sponge filter
Frank Castle
I always just do 75% WC daily, like i'm about to go do in a few minutes......got 10 dozen fathead minnows Tuesday, gotta go fishing and use some up, too many in one bucket

Been raining for days and gonna keep going until MONDAY!!!
If i'm at the water's edge, i'll swap water every hour or more, TBH.....or just put them all in the Flow-Troll, tie it off and submerge it in the creek/river/lake/whatever.....then the pump is just for the transport, and I save battery-life. natural aeration is always best
Fisherman's best friend......just tie a 10-20 foot rope on to the handle and lock it down
http://image.sportsmansguide.com/adimgs/l/4/46172m2_ts.jpg
For the record, I put that INSIDE my 5g bucket and clip my air pump onto the outside of the 5g......the 5g filled w/ water is like and anchor and keeps the Flow-Troll from floating away when I tie them together....better to maintain ammonia levels while transporting too