Add animals to the pond that eat snails as part of their regular diets. The most common pond fish, the koi, will not eat the snails. Frogs and sterlets eat adult pond snails. Some smaller fish, such as mosquito fish, eat snail eggs. Sterlets can survive year-round outside in mild climates and in water temperatures of 52 to 72 degrees Fahrenheit. Mosquito fish also do well in mild climates with water temperatures of 65 to 75 degrees. Online and brick-and-mortar fish retailers sell these predators for your pond. In some regions, you can get mosquito fish from your local vendor or mosquito control agency for free.
Why do snails eat fish? - Quora
@anonymous: Hmmm... Well, since the door is sucked up tight, the snail is still alive. Which is good news! If the heater is a recent thing, it could still be in hibernation mode, or it could be a water quality issue. If you have test kits or test strips, I'd try testing the water the snail is in. If nitrites/nitrates are too high, it could be why the snail is in hiding. Also, if you use tap water, at different times of the year cities put additives into the water that are bad for fish. Same thing with well water depending on where you live, if there are lots of animals around stuff can sink into the ground and get into the water. If the water tests out fine (or you don't have any tests you can use), you could try using bottled water if the snail tank is small enough. Just be sure the bottled water has no extra stuff in it. Then leave the snail alone for a few days. If the betta picked on it enough, any movement from you could be taken as a possible threat and it'll have to get used to the fact it's safe again.
How fast do mystery snails eat dead fish? : Aquariums - Reddit
At this point your best bet is to move the snail to it's own bowl with treated store-bought water that has no additives listed on the label. Then see if it starts to perk up a bit after a day or two. Definitely check your parameters in the 10-gal and do a water change. If all your fish are acting normally, and the snail gets better, you can try putting the snail back into the main tank. If it has the same symptoms after being returned to the tank, then you'll have to figure out exactly what is in the water that's killing it. Be sure not to use anything that has copper in it, no additives, or decorations (any new rocks you 'found' and added lately? Some have traces of bad-for-snails minerals). If you can't find the cause and all your fish are fine, you may have to have a permanent separate tank with store water for the snail.
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