I agree with Rob. That tank is far too small for that fish. As he said, they get to 3ft easy but can go up to 5ft/6ft in which it would need a tank over double that size. I do feel that the Redtailed Cat is better left in the wild. Only a very small minority of people have the size tanks/ponds they need, so when they get bigger they go from home to home, and eventually living in a tank far too small for them.
But getting back on topic, that tank is quite big

. Wonder how much he would tank for it.
There was also someone selling a nice 8x3x2 with stand and sump for the bargain of £250.
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8' x 2' x 2' - Piece of Ocean.
6' x 2' x 18" - Wild Caught Zaire 'Moba' Frontosa

4' x 2' x 20" - Malawi
4' x 22" x 18" - Malawi + Victoria
4' x 18" x 18" - Breeding Cuban Cichlids.
Trigon 190 - Paratilapia Polleni
30" x 1' x 1' - Hospital Tank
2' x 1' x 1' - Tropical
and
7x - 1' and 2' cichlid fry tanks