I would really recommend the trash can. For one, you're going to need time for the salt to mix properly into the water, and to get up to temp. For two, you're not going to have the option of mixing in tank later down the road. I use a rubbermaid with a old p.o.c. rio and some tubing. I do water changes every week, all week long I fill the can with ro
water, with a pump running in it and a heater, mixing the salt till it reads right on the refractometer. Then the day I do water change, I take my two 7 gallon water jugs, have my partner fill those from the tank with the python while I'm in the garage filling two other 7 gallon jugs with the pump from the can. By the time I get both jugs full and in the house, my partner is just finishing sucking the last of the second jug out. We have it timed, we can change out 14 gallons in 15 minutes like this. And 21 gallons in 18 minutes. Buckets really are a pain in the butt, and in my house, they're strictly forbidden because of baby-safety issues. I much prefer the 7 gallon blue drinking water jugs. Keeps idiot relatives from dumping Lysol into them too. (I thought that was a mop bucket).