Aquariums: Surrendered Sailfin pleco i took home from work

Hey !! So i took a big 10inch sailfin with a spinal deformity at work since i am the attic’s specialist and can take care of it, currently settling down in a 50 gal plastic tub with sponge filter from established tank going

I know hes a commitment. And would like to take care of him and restructure my whole approach to

keeping fish in a much more enriching way for me and the fish .

I’m currently looking to have an indoor “pond” of sorts. I don’t mind having to bite the bullet and pay more for an expensive stock tank but i feel like having an indoor pond type of situation would be better for me and my fish.

My Jack Dempsey is gonna get bigger, and would like to keep him and the sailfin together down the line. I’m going to check marketplace soon for big stock tank like setup but would like to know of any products online that would be just as durable and big enough for my 2 fish. I wanna do right by him. The guy surrendered it and was improperly kept for years and i believe the deformity might have been from improper care? Correct me if I’m wrong !!

I have mangroves floating to begin rooting and plan on including pothos as well as the current established filtration situation i already have

How can i make him happy for the first time in his existence with this setup im trying to achieve?

I am willing to forgo the glass aquariums and offer functionality and appropriate space over aesthetics which is what the plants i plan on rooting will compensate for

What are some tubs 100+ gals i can look into that wont be $200+ or is that something i should do anyway? No issue regardless , just a bit more time before id able to do the big conversion that i think would make for a wonderful spring project , and would i have to sacrifice viewing the fish for viewing straight from above? Or would that make them feel safer anyway

Thank you!

This is him