Arowana, new tank.

[DertyMerv]

6long x 3wide x 18deep is the smallest tank your going to want to build if you plan this fish living in that tank forever. (imo 6-8'l x 4'w x 2'd is optimal) The long and wide dimensions are the most important since aro generally stick to the top 2/3 of the tank it doesn't need to be terribly deep but they do need ample room too swim. Ive seen folks do just fine with a 15 inch deep tank but it was long and wide.

 

[Guerrero]

6long x 3wide x 18deep is the smallest tank your going to want to build if you plan this fish living in that tank forever. (imo 6-8'l x 4'w x 2'd is optimal) The long and wide dimensions are the most important since aro generally stick to the top 2/3 of the tank it doesn't need to be terribly deep but they do need ample room too swim. Ive seen folks do just fine with a 15 inch deep tank but it was long and wide.

Thanks for the suggestion, I will build a 5x3x2 plywood tank to house it along with a pair of rays, although I don't think this will be their forever tank.