There are a lot of issues here and NH3 is definitely a possibility but it does look more like DO.

I would never recommend stocking a pond within 3 months of it being filled. Ammonia is definitely an issue in new ponds, especially when feeding is undertaken. This pond never had a chance to produce beneficial bacteria in equilibrium.

The only way you'll ever know is to either have the water professionally sampled, which can cost 300-1k or start dissecting fish. Until then, it's a guessing game.

I would be extremely curious to know if your fish are eating the unbound soilfloc you saw floating.

Last edited by Joey Quarry; 06/09/19 09:37 PM. Reason: Soilfloc