TGW1 has a pretty good suggestion about adding grass carp(GC) after the water clears from an alum treatment. HOWEVER be cautious about adding too many who will make your water cloudy again directly based on how many grass carp are in the pond and pond being denuded. A few bottom plants are very good none is not good in that no bottom growing plants make the pond very prone to turbidity problems.

Grass carp are very easily added when more are needed, but they are very difficult to remove once they become pond residents. I suggest that when no submerged plants are present then add only 1 or 2 per acre.Then these 1 or 2 fish can often keep rooted vegetation from becoming over-abundant. Note that 2 or more GC per acre with no plants could contribute to some pond turbidity. Pond bottom aeration will play a role in pond turbidity problems. Some pond sediment turbidity is natural pond dye and helps reduce submerged plant growth in deep water. Many pond owners have sediment turbidity that keeps the pond visibility at 12" to 30" and they mistakenly think the most of the cloudiness is plankton. Not true. Water color or hue is a good indication of the amount of living plankton. If water has a hue of your local soil color then turbidity is very likely mostly suspended sediment.

Last edited by Bill Cody; 08/12/20 08:45 AM.

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