I firmly believe that having a well aerated pond outweighs the downside of having warmer water at the bottom of the pond. Without testing equipment you won't be able to check your O2 levels, but here is some first hand information.

Trout are not supposed to survive in ponds that get warmer than 70°F. OR survive in water that has less than 5mg/l O2 for long periods of time. A customer that had both a bottom diffusion aeration system and a surface agitator type aerator had trout survive into the low to mid 80°F water temp range (mid 80's at the surface, low 80's at the bottom) due to the amount of O2 that the water was carrying. It was at saturation level top to bottom, which was above what the trout needed to survive.

Since both WE and YP need much less O2 than trout to survive, I think that you will be just fine with the air stations set on the bottom of the pond providing that the system is designed correctly for the pond and the air stations are placed correctly in the pond. Like FR said above, having the air stations placed correctly in the pond eliminates the dead space between the aeration cones of influence in the pond.

Once the system is set up and running for a week, you will not have any anoxic water at the bottom of the pond.


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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).