I decided I needed a cover for my indoor Koi tub, with the garage being unheated and the water being heated it was causing a lot of condensation throughout the garage.
I built it out of 1/2" PVC, I told Craig about my idea, I even drew it out, but until we got it somewhat built he didn't get what I was saying, but it came together exactly like I had planned. The whole thing cost less than $20.00. I used three 4-way T's, 8 elbows and 8 1 1/2" T's with a 1/2" outlet for the legs, they are cut in half so they rest perfectly around the edges of the tub and I just threw a painters tarp over the top. It is like a rainforrest in there now.
I didn't glue it so I could disassemble it when I am not using it. I need to build a new filter, the one I have been using is from the old pond and it developed a huge crack in the lid several years ago, I used some of the plastic to seal it, but it is now leaking out of the sides. I think my pump is just too powerful for it and the pressure inside it is immense. But fish have grown like crazy and seem really happy, they take turns swimming into the current from the filter. Water is holding steady at about 73 degrees.