Here you have 3 different designs of snail traps for you to print and finally manage to control this pests in your aquarium, according to your needs!

Snail Trap A: 

• Bigger model;
• High holed cilinder where you deposit the snail bait inside. 
• Has holes on the cap for you to run nylon wire to pull the trap and not have to wet you hands. 
• In order for the inside infill cavities full with air to be filled with water and thus making the trap stay on the bottom of the tank without you needing to print with 100% infill, there are holes marked on the base lateral for you to drill mechanically or though a heated nail (careful too not cause fires!).

Snail Trap B: 

• Simple holed box with slide in bar cap. 
• Designed to collect bigger quantities of snails (as displayed on the pictures). 
• Again, just deposit the snail bait inside and then take the box out with the little pests inside.

Snail Trap C: 

• This trap in designed to be buried and keep only the top surface of the cap with the holes exposed.
• Deposit the snail bait inside.

I have used all these traps on my aquariums and they worked fine for malaysian trumpet snails.

A snail bait I use normal fish food (granulates and pills), sliced cucumber or courgette, cabbage.

Good luck!