Zebra nerite snail reproduction & mystery tank snails: Are they safe?

You likely wouldn't have been able to see the eggs. It looks like it could be a trumpet snail given the shape. This species grows to be about an inch. Clip a piece of lettuce to the side of the tank overnight. In the morning, the snails should be all over it feasting. Remove your Nerite and dispose of the rest in the trash. You may need to do this several times.

Some female mystery snails can be prolific egg layers. If she has no male, the eggs will be infertile. You can pick them off the side of the tank and discard them. To discourage egg laying, raise the water level to just below the top of the tank. This species will only lay eggs above the water line, so if she doesn't have enough room, she may not lay.

Cricky may eat the eggs/baby snails. The best thing to do is either remove the eggs to a new tank, put in a breeding net and put the eggs there or provide decorations and hiding areas for the eggs/snails. Be fore warned that snail may reproduce quickly and they can over populate. I hope this helps and please feel free to post any additonal questions.

You will need a cover or tank hood to prevent any snails from crawling up and out of the tank. Snails will lay eggs just above the water line, so you'll need to leave room for that as well. Quarantine, or keep them separate from the main tank, for at least two weeks in another tank. This is done to prevent the spread of bacterial infection or parasites.

The salt would probably irritate the snails. If you still have frogs in the tank, consider a salt bath instead. Dissolve 1 tablespoon of salt in 5 gallons of water then remove the frog(s) from the main tank and allow for a swim of no more than 60 seconds in the salt bath. Rinse then return them to the other tank or hospital tank.

If you are referring to Mystery Snails, then 3 or 4 would be fine for that size tank. Some aquarists may recommend 1-2 snails per 5 gallons, but it depends on what else you plan on keeping in the tank.

There are several species of Tetras and sexing them can be tricky or downright difficult. Neons are the easiest. Look at the neon line along the body. If it is straight, you have a male. If there is a slight curve, you have a female. In other species, it isn't as easy. Females are generally rounded and fatter. Males are longer and slimmer. Male Danios have more vivid and shiny colors than females. Both have yellow between the stripes, but males are more vibrant. Male Danios will also be longer and slimmer while females will be shorter and "thicker". If they spawn, you can leave the eggs and adults in the main tank. The adults will eat the eggs...or fry (baby fish) if they hatch. You can also vacuum the eggs out and discard them.