Snail eggs in an aquarium can be dealt with easily, depending on whether you want more snails or not. If you don't want them to hatch, the general consensus here is spot on: carefully remove the egg clusters and freeze them for a couple of days before throwing them away. Freezing is thorough and humane, since it ensures the embryos don’t survive. Crushing should be avoided—it leaves a mess, and some eggs might still hatch.
If you’re interested in seeing baby snails, just let the eggs be. Most commonly kept aquarium snails’ eggs will hatch within 2–4 weeks. Make sure the eggs are kept humid but not underwater; otherwise, they might not develop properly. Watch for any that become opaque or moldy—these are dead and should be removed to keep your tank clean and healthy.
If you’re unsure whether the eggs are viable, a fresh clutch usually looks clear to milky white, slightly pearly, and plump. Eggs that turn yellow, gray, or develop a bad smell have likely spoiled.
Overall, controlling your snail population is simple with proactive egg management. Just remember: a small decision now saves you from a tank full of unplanned snails later!