I've seen many use tubs like that for fuges or sump. Did see one post (forgot where) that said they had problems with the tub cracking one day after some age. Another said putting baffles in them was impossible. Maybe baffles wouldn't be needed anyway if the water flow going thru was slow - like 1 or 2x per hour.
Ideally, the fuge could be set higher than the sump. Pump up to the fuge and have gravity flow back into the sump. Of course you'd have to drill a hole in the sump to do that.
"Life may not be the party we hoped for but while we are here we might as well dance!"