I have a few 1 cm snails (two brownish, two reddish, and one grayish) in a 10 Gal with small goldfish and weather loaches. A couple of days ago I noticed a couple of baby snails, 2-3 mm, either from breeding of the ones in the tank, or from a new plant I added. Now they are gone. I checked the filter and I didn't find them there, unless they were sucked in very deep in the sponge, but I doubt it. So, did the goldfish eat them, or the weather loaches? I was hoping to have some babies survive as the snails do a pretty good job eating aglage, and haven't touched the plants.

On another note, I noticed the weather loaches like to hide behind rocks (when they get tired of trying to escape), so I'm wondering if I should have some kind of cave shaped ornament that they can really hide in.

I would suspect the goldfish as main culprits here...They are quite some merciless eaters. I had a clutch of snail eggs sticking to the glass of my betta fry tank, and the day they hatched (which was yesterday) I am pretty sure the betta got quite a few snail babies before I took the bettas out.
As for the loaches, I am not familiar with that particular kind of loach, but I do have weather loaches which also like to hide behind and under rocks. Maybe its a loach thing. I have a barebottom tank, but a little "island" of smooth river rocks and plants in the middle, and thats where the loaches are mostly hiding. You also could use a 4-6 inch terra cotta pot, put it sideways on the tank floor, so the loach will probably use that as his "cave"....

Yeah, mine LOVE hiding. I've found that if you have plenty of hiding spots like caves, tunnels, busy plants, etc. They dont try to escape!! I have heard that they like to eat snails too, but most likely it was mainly the goldies.

My weather loach/Dojo has killed a quarter sized apple snail before, so it is possible. (Snails shell had a tiny hole and dojo kept picking on it until the hole was big enough to eat the snail. I didnt realize the Dojo was the one doing it until I caught him with his head in the shell while the snail was still alive)

And more Dojo loves to hide also. Hiding places are a must.

in a tank with a couple of 2-3mm snails i think it would be very hard to find them! They are probaly in the gravel hiding. Trust me i have sooooooo many snails in my tank that i never ever saw untill i took my goldies out they are excellet hiders espically when they are small!

I guess I didnt pay attention to the size . As Fishies said they are probably just hiding somewhere.