Admiral Fish restaurant is located near Birtvisi canyon literally on Algeti river. We discovered this place a few years ago while hiking at Birtvisi canyon and have returned ever since,

They have both a restaurant and fish farm on site, the place seems is run by Russian/Ukrainian business people. Here you can get a wide variety of fish food and caviar. It's said they deliver to Tbilisi fish also.

Admiral Fish restaurant

Admiral Fish restaurant

There is a place for parking, a kid's corner, restrooms, and really cozy gazebo's for dining. The best - it's outdoors. The restaurant is literally located on Algeti river.

I guess they are using freshwater for fish farming.

Gazebos above the river

Gazebos above the river

Algeti river connected to the Nearby Algeti reservoir

Algeti river connected to the Nearby Algeti reservoir

If you happen to be in this area, make sure to make a stop here and try some fish. 

Location & Map
Georgia
Coordinates: 41.589573 44.538437