Cerith snail eggs

[krollins]

My cerith snails laid eggs. I was out of town when it happened. How do I increase survival rates. It is a 75 gallon tank with a lot of fish and inverts.

 

[ISpeakForTheSeas]

Are the eggs hatching as planktonic larvae (i.e. swimming babies) or benthic juveniles (i.e. crawling babies)?

For the benthic ones, you just make sure they have plenty of little spots to hide and plenty of food to eat.

For the planktonic ones, you set up a larval rearing tank (a simple, little tank with an airline and possibly a heater/light), offer them the right kinds of food in the right quantities, and hope you've got the right cues going in the tank for them to settle or that they don't need any specific cues to settle.

The chances of them hatching are pretty good; the chances of them surviving after hatching are not as good (I'm only aware of one Cerithium sp. that has been reared successfully). In most cases, the snails in our tanks have pelagic larvae (free-swimming larvae) that get removed by filters/skimmer/etc., eaten by fish, starve, etc. Some snails (including some Cerithium spp.), however, have benthic larvae (the young are born as basically mini-adults, crawling on the substrate and likely feeding on similar algal species), and these are much more likely to survive.

If yours are pelagic larvae, you'll need a larval rearing tank (a tank that's safe for pelagic larvae) to try and raise them in.

Similarly, pelagic larvae will require a specific feed in specific quantities multiple times a day (typically these feeds are either phytoplankton or things like copepods) - the one Cerithium sp. that I'm aware that has been aquacultured was reared using Oocystis sp. phytoplankton (this is not commonly available, so it is very expensive to buy a culture of, and it may or may not work for a different species).

For the one species I'm aware of with planktonic larvae that were reared:

The eggs should hatch after ~3 days (73 hours), they'll stay as veligers for ~3 days, and then they'll drop to the bottom as "creeping larvae" for ~15-20 days. It takes about 30 days for them to develop into adults with a five spiral shell. The algae I know they'll eat is Oocystis spp. (which you could order from UTEX, but it would cost quite a bit

 

[krollins]

They have not hatched yet.

 

[EeyoreIsMySpiritAnimal]

They have not hatched yet.

They won't survive.