Koi Rescue
Phoenix Arizona

Setup the tank and fiberglass it together

The tank was originally designed to be a 2 piece tank, and to sit on sand. Notice that when the pieces are together, they flare out a bit. This is because I am sitting the tank on a flat concrete floor. (well, somewhat flat concrete)

Here is the lip that sticks down below the tank, on the lower left side of the picture is the bottom of the tank and the upper right you can see the blue area, that is the vertical side wall of the tank. I cut the lip off the bottom so it could sit flat on concrete.

Next issue is that this tank was designed as a 2 piece tank, and to make it cheaper to ship, I had the manufacturer cut the halves so it made the tank a 4 piece tank. The bottom of the tank has a foam core, so with that additional cut the foam is exposed. I needed to seal it off.

So I dug about 1/2" of the foam out and filled it with thickened epoxy.

After all the edges were treated, it was time to fiberglass all the parts together. Because my floor wasn't perfectly flat, I used blocks to hold the edges down and together.

Time to cut the window. I wanted a bigger window than I had used on the 1200 gallon tank, and I just happened to have a perfect piece of thick lexan in stock. Years ago my mother in law gave me a 3/8" thick 24" x 18" piece of lexan that she said would be great to install in the bottom of my boat, to make a window for the girls to look underwater with. Only problem is that the waters we sail in are very murky, so we wouldn't be able to see anything. I kept that piece for years and now I know why, it was fate that I'd be using it in this tank.

In the 1200 gallon tank, I simply glued a piece of 1/8" lexan directly to the wall of the tank. This did work OK, but it made a sort of magnifying glass effect since the side of the tank is curved. Fish up close would look normal, but fish on the far side of the tank would be distored, and they looked wierd. So on this tank I wanted to have a flat window -- so I had to fiberglass a frame for the window to mount to.

I started by standing up this form board on the inside of the tank.

Then from the front, I could apply fiberglass around the edges and the form board would create the flat surface that the window mounts to.

I fiberglassed the outside first

Then I glassed from the inside. This picture is after I removed the form board.

After letting the frame cure for a couple of weeks, I trimmed the inside edge a bit, cleaned up all around and it turned out pretty good. I took the picture at this angle to show the curve of the tank and the flat edge the frame creates.

Here is mounting the window. I used 2 tubes of 3m5200 in copious amounts and let it cure for 2 weeks. I sanded all the edges to get rid of the sharp spots, then used lots of bath tub caulk around the edge to seal it even more.