I didn't set up any outside 'ponds' this year because the weather has been sucky. So I made some indoor ones. I set up 2 rubbermaid bins, one is 30gal and the other I think is 40 or 45gal. They don't have the same effect as being outside though, but its an extra place to put fish! I dump in mosquito larva whenever possible so at least they get to hunt for their food sometimes. There is no heater, temp stays at a solid 70. I put in airstones to keep things moving, and some plants and hiding places. I started with a larger light coloured tub but soon found out it had a leak, so I had to switch to the black one. I put white gravel on the bottom because it was too dark to see down!
I don't think they are growing as fast as they would outside, but its still faster than in a smaller tank.
Anyways heres some pics:
This one has a spawn of greens

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This one has betta falx

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