How would you build something this large? I want it to look nice because it will be in my house. It will be build on the outside wall with a window into the house. I would do cement blocks but I am not sure if it would hold and don't know how I would seal it. Also how would I deal with the open top with evap and also salt creap and so fish don't jump out. I had a 1000 gallon tank just out of plywood and steel and it bowed a little when it was filled. Anyone build something this large? Pic and dos and fonts would help.
Approach it like a swimming pool build. Same idea, a big concrete bowl to hold water. The main points will be us as little rebar as possible, and the thickest concrete lay you can get between the water and rebar (so the sharks don't have navigation issues with the metal). For the window, you'll have to get in touch with one of the large acrylic companies to have a custom cut section done. Living Color or ATM would be your two best bets depending on where you live. Let me know if you need a person at either of them to get in contact with. The main difference between a swimming pool and a shark tank will be the filtration and decor on the inside. You'll want to invest a lot in the life support to prevent costly failures and upgrades later down the road. The proper set up also makes it easier to care for day to day.
The open top is something you have to deal with. Again, depending on location, you'll have temp to think about. Evap on a large system like this isn't usually a problem due to the volume of the pool. Salt creep is always something to think about, you just have to build it correctly to minimize the filth associated with a large marine pool.
If you dig in my REALLY old threads, we did a big FW concrete pool with an acrylic window at the Como Zoo in St Paul, MN several years ago. It's more or less what you are looking to do.
