Raising Cerith Snails
By, Mike Holcomb
This is a brief account of my observations on the raising of Ceriths. I want to emphasize that I do not know (exactly) what it is that has allowed the Ceriths to repeatedly reproduce and the young to survive, but perhaps my observations can be of use to you.
ABOVE: Mike Holcomb shows off his ingenious multi-tub/tank facility made from inexpensive materials. This is a nighttime peek inside his 8'x12' insulated reef-shed in Nampa, Idaho. Most of what he has is tank-raised by himself or others, including the clownfish and many of the. Not many people can regularly raise snails like Mike does. He reported that he has moved about 1000 of the tank-raised young snails out in 1998 to sell or trade. He is also experimenting with homemade water surge devises. While visiting the Boise area in October 1997, Dave Foster and I were more impressed with Mike's intriguing yet simple operation than with anything else we saw on the garf sponsored Bosie, Idaho reef aquarium tour. Mike was then 16 years old.
The tanks - One is a 16.5 gal storage box (Rubbermaid type) with three airlifts for circulation, lighting is by two 40 watt plant lights and sunlight in the morning hours. The other tank/system consists of 4 layers of tanks all connected together, the top three layers each consist of three 8 gallon Rubbermaid containers, each container has 1 MaxiJet 1000, 100 gph (approx.), Water movement from the sump pump, and most have some sort of wave maker. The two end containers on each layer contain Hagen 201 powerheads. Lighting on the upper three layers is provided by one 40 watt cool white, one 40 watt actinic, three 40 watt plant lights and some natural light from an east/southeast facing window. fluorescents are operated for approximately 12 hours/day and actinics run approx. 14 hours/day. In each of the upper layers the middle container is devoted to the cultivation of algae and the end containers support a mixture of corals and algae. All sections have a mixture of crushed coral and dolomite gravel and some live rock (formerly dry aragonite). The lowest level consists of one 9 gallon Rubbermaid container and a 20 gallon sump. Both of these areas are provided with circulation only by the approx 100 gph that flows through all of the containers. Dry rock and gravel are the only things that were ever added to the bottom containers, anything living came on its own from another part of the tank. Lighting is from one 40 watt plant light, one 40 watt cool white, and one 40 watt actinic.
With the exception of the sump, all containers have had baby snails (the sump regularly receives cold fresh water and contains no snails which is probably why it has not had baby ceriths). Young ceriths (1-3 mm long) appear on the sides of the containers every 30 - 40 days on average. As the system ages different containers become more productive, an increase in productivity in a given container seems to be preceded by the following: areas along the bottom of the container become largely cut off from water movement, large quantities of detritus and aragonite dust accumulate, and brown macro and micro alga proliferate. I believe that these 'dead' areas allow small pieces of algae and snail larvae to settle out of the water column into a relatively safe area with few disturbances which allows the snails to feed, absorb calcium, form a shell and move out into the rest of the gravel bed without being eaten by corals, worms or crabs. Recently (March - May) I have observed a large increase in the number of baby snails, changes during that time that this increase may be attributed to are: an increase in natural light, increased nutrients from dead insects, increased water temperature (80 - 96F), death of some SPS corals, loss of one of the three hermit crabs, and an algae bloom (including caulerpas, red and brown macro alga, green and brown hair alga, diatoms, coralline, and slime algae (not cyanobacteria)).
The 16.5 gal storage box, despite having no powerheads or hermit crabs, very rarely has more than a dozen young ceriths in a month, it is cooler than the other system (70 - 80F) and it has much less algae and diatom growth, the aragonite dust on the bottom of the tank does not have a great deal of organic material built up (some brown cyanobacteria though). Maintaining calcium levels and algae growth are critical to the survival of the snails. In their first few weeks, snails grow very quickly and take a LOT of calcium and algae. When algae growth diminishes, in the tank that the snails are in, they will need to be spread out to other tanks so that they have a better chance of reaching adulthood and to make room for the next batch of snails.
ABOVE: Closeup of two of the many interconnected Rubbermaid tubs (plastic storage boxes) making up part of Mike Holcomb's reef systems in Nampa, Idaho.
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(All photos and photo-comments by Tom Miller)
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ABOVE: A dark nearly inch long cone shaped Cerith Snail cleans the glass while an Astrea Snail (right) cleans a rock in Valerie Miller's reef tank.
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ABOVE: A large mass of Cerith snail eggs on the glass of one of Tom Miller's Aquariums. The tiny eggs are only about 1/10 millimeter diameter and a bit oblong. There can be thousands of eggs in a large four inch by 2.5 inch clutch of eggs like this one. Egg, larvae and young snail predators can be of concern to those whishing to raise snails. The glass crawling little white decapods eat the eggs (on the right and above eggs). They finished this batch off in about 10 days. These snails lay their eggs on rocks and glass in the same zig-zag patern that they clean with.
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