how detrimental to breeding egg layers, are pest snails... and who is eating the snails???

[Magnum Man]

I'll start with who is eating them... my African Tetra tank is extremely full of pest snails, the tank next to it has South American Tetras, with no pest snails, the tank next to that is my Hillstream tank, again, no pest snails, and the tank next to that my South American medium Cichlid tank, also no pest snails... I have some King Tiger Plecos, that certainly look like they have been trying to breed, as well as some Kuhli's and several dancing sessions from the egg scatterers, in the African tank... I'm not particularly trying to breed anything, but curious if the pest snails are at fault for not ever seeing any eggs???

the other 3 tanks, have gotten plants , and are treated the same, so I'm assuming someone is eating the snails... in my South American Tetra tank. I assume it's the angel, who is always hunting, and or the Spotted Silver Dollar, who was more recently added???

in the Hillstream tank, my best guesses are the Panda Garras, the Kisser Gourami, maybe the Flying Foxes, or the Denison's, and maybe some of the larger varieties of Hillstream's...

in the Cichlid tank, I could believe any of the residents could eat pest snails, including the giant Oto's, but probably not the Apisto's, the Cory's, or the smaller zebra Oto's...

as I get around to setting up a couple breeding tanks, how careful am I going to be to keep out, and control those snails???

 

[GaryE]

I did an experiment to confirm what I'd been told by a local aquarist.
I collected killie eggs and once I could see they were good, put them in petrie dishes with water. In some dishes, I put a ramshorn, and in some, a pond/bladder snail.
The results? Ramshorns generally left eggs alone, but bladder snails went right for them and ate them.

It doesn't give a clear answer, because eggs are alive too and many have chemical defences. So there has to be a relationship with the snails from their habitats, and I know nothing of snail distribution. But it taught me something useful - I am an enemy of pond snails, and don't hate ramshorns, though I don't especially like them.

Tetra eggs will be different from killie eggs or Cory eggs (my friend had gotten the same results with Corys though).

My advice? No pond snails in breeding tanks. No 'untested' fancy type expensive snails. Since some eat eggs, avoid them. Would I allow ramshorns? They did eat infertile eggs, which would be useful to stop the spread of fungus, so maybe. A few in my long term breeding killie or dwarf Cichlid tanks are okay, as long as there is a light source at night so the Cichlids can defend their eggs.

 

[TwoTankAmin]

I get lots of pond snails in my pleco grow tanks due to the heavy feeding. Before I was spawning anything I had pond snauls in my planted tanks. The exceptions were my tanks with the sidthimunki loaches and my clown loach tank.

I got assassin snails for the planted tanks but was afaraid to keep them in breeding tanks I normally only move kids to grow tanks when iI am overrun. I do not put assassins into tanks with fry just to be safe. However, I do harvest the pond snails and put them into the other tanks where I have assassins. They will have wiped out the pond snails already. So I feed them the snails from grow tajks, the assassins multiply and I sell them at my club auctions every month or when I an selling at an event.

I actually find amano shrimp to be more of a threat to small fry than assassins. But I am not willing to take the risk with pricier plecos.