I'd definitely go for it. You can't beat it for free. Multiple water changes per week would be great until you can get them used to the once weekly schedule. There's no reason why you shouldn't be able to get away with once a week IMO
I'd offer a little cash and try to end up with 4 big discus rather than 2, though.
Originally Posted by phoenixkiller
A 55 gallon will be fine. But be prepared to spend a considerable amount of money on your beloved discus. BE WARNED: these fish are not easy to keep and large and frequent water changes are a must.
But have fun with the "King of the Aquarium"!
Have you kept them before? Large discus really aren't difficult to keep. It's the juveniles that need most of the attention and effort. And as far as expense, with the tank and equipment being offered for free, the startup expense would be next to nothing. Continuing costs would just be water, food, dechlorinator, etc. There isn't anything inherently expensive about keeping discus, just the fish themselves can command a high price.