Question
Robyn,

I have a small 400 gal pond in my garden. It is 23" deep and I have several goldfish in it. (10)
I keep it very clean with a bio uv filter system, but junk still accumulates on the bottom. I have considered added a few crayfish to clean up the junk, will they attack my fish?

Thanks alot for your imput,
Les

Answer
Yes, crayfish may eat goldfish under a few inches long or tear some fins off of larger fish, especially if they don't get enough to eat. Their natural habitat is in shallow areas near streams, etc.  They even spend some time sort of out of water in little mounds in the gravel and sand areas on the shore.  They really don't like to go deep.  What is the "junk?"  If it's fish waste and decaying matter, the crayfish probably won't want to eat it either.  A pond cleaning or the addition of some good bacteria and enzymes may be in order.  Crayfish will eat small plants and animals but don't want "junk" anymore than any other animal.

Robyn
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