I purchased some snails for my pond, thinking they would help keep the algae in check. Now I'm really worried about parasites from them. I've never lost a fish in my pond due to bad water quality, parasites, fungus or bacterial until now. Shortly after I introduced these things to my pond. I started noticing changes in my fishes behaviors. Now several things were going on. Spring always bring spawning and algae blooms (which for me, in my pond was causing wide ph swing) and I know that causes added stress on the fish. We had also brought in some new plants (which can carry, who knows what), also purchases some new koi (no gasping please), I did quarantine the new fish for 3 weeks in my quarantine tank, in a product call de-los and then, put them in the pond. I lost 4 koi, clearly due to fungus and bacteria problems. Its been 3 weeks sense all this started, all fish look great with no visual signs of health issues. The (reaper has gone) lol. We fed the fish with koi fix in their food and treated the pond with Nitrofuracin Green as recommended for our pond size. Then have sense followed up with 2 treatments of Potassium Permanganate and hydrogen peroxide.
My question is, should I put the Trap Door snails back in my pond?
Advise from the guy who advised us on the potassium and hydrogen peroxide treatments said, "pray for death to my snails" they carry parasites that just can't be killed and will reek havoc on the health of my fish. I remove the snails from my pond before we started treatments because I was worried the meds would kill them.
Is he correct telling me this?
I'm wondering if the snails could have been what caused all this?
Any help would be appreciated!