A couple of broad pond snail questions

About a year back I got nd MT snails in my display tank, presumably from some plants from the LFS.

Their population exploded; I was literally picking several dozen out each week (more so the pond than the MTS).

I bought an assassin snail, and it didn't make a dent. I bought two more and the same--if the assassins were hunting, the pond snails were reproducing way faster. After a few more months of picking out snails, I was inspired to get a second tank, a 6 gallon to host a single dwarf puffer, figuring that since I have this pest snail problem, I might as well put them to good use.

So that's how things have been since March--I go to feed my 23g tank and while there pick out a few snails and toss them into the puffer's tank, where the little maniac rips into them.

But for about the last month or so my display tank's snail population has crashed, to where it's all I can do to pick out a couple of (very small) snails from time to time. I set up my hospital tank again, got some algae growing, and tossed in a few snails, hoping to restart a population, but nothing so far (it's been a week or so)

So: why could my snail population have crashed so suddenly? Months and months of more snails than I know what to do with, then almost nothing. I do have very little snails around... could they be a burgeoning population of assassin snails that are taking out the others before they get going? I don't think the little ones LOOK assassins but I could be wrong, and I'm not really seeing many get all that large.

Separate question: I've been looking for a source of pond snails. I went to one LFS and asked, and they seemed to think "pond snail" = "snails that can be put in ponds." I'm pretty sure what they pointed me to were Inca Snails. Looking here pond snails does in fact seem to be an inexact term.

Is there a more specific name for this sort of snail, other than pond?

 

Do you feed the fish in the 38 gal less than you did before? More food equals more eggs equals more snails. They stop laying eggs if food becomes scarce. It's possible the assassin snails went for the adult snails so you're left with juveniles that won't lay eggs for a couple months.

How large do the pond snails get? The kinda look like bladder snails to me. You could also try asking the LFS for ramhorn or bladder snails.

 

Thanks for the reply.

It's a 23 gallon tank. Thinking back, I did change one habit: I used to put in sinking shrimp pellets every other day for my corys, but I stopped doing so; I can't recall how far back that is (i've been using live blackworms when I have them, alternating with flakes, or just the flakes). Otherwise, the food quantity is the same.

I've never let them get big; by the time they got to lentil sized (think lentil-sized sphere, not lentil shaped) they were either plucked out or, later, put in with the puffer.

Assuming that this site is representative of bladder snails, mine don't look like anything on that page. I don't have any better shots other than the old one I posted above; what few snails I have left are barely the size of short-grain rice.

I did find one LFS that had some pest snails in their plants, and they plucked out a bunch for me. Gave the DP a couple and put the bigger ones into the hospital tank.

 

Sorry, I'm not quite sure where I got 38 gal from haha.

If you got mature snails and are feeding them well, you'll start seeing jelly like eggs in a week or so and they'll hatch in about two weeks. Typically takes a month for them to get to a good size for DP's to eat.

Alternatively, you can feed your DP the black worms as a staple.

Side note: Cories need a higher protein diet than flakes can provide, so if you don't have black worms at the moment, I would feed the pellets. May also boost the snail population back to normal.

 

I have the blackworms pretty regularly, so at most a few days go by without using them. I'll try adding the shrimp pellets from time to time.