Let's Talk About ~Snails~

[NaH2O]

Hey Everyone! Time for a new discussion. Snails - most of us have them....whether desirable or undesirable. Let’s talk about the different species of snails (the good & bad), selection, and care. How do you choose the amount of snails? What species of snails have worked well for you?

I’ll start off with some basic physiological information, and why acclimation problems can arise. Snail’s internal structures are complex, not simple, as one may think. They are made up of thinly layered tissues and even though they are strong little critters, they have a difficult time dealing with rapid chemical changes to their environment (i.e. poor acclimation, water changes). Changes in salinity can cause the vessels and channels in the circulatory system to rupture. The article linked below contains some great diagrams and more information:

The Grazing Snails, Part I - Turbo, Trochus, Astraea and Kin

The vessels in the kidney are numerous and delicate, and may rupture if the animal is not slowly acclimated when being moved from one set of water conditions to another. If the acclimation is too fast, the animal will die in a few minutes to a few weeks. If the snails are drip acclimated, the acclimation time may need to be on the order of five to ten hours for maximal survival.

According to this quote, it is very important to acclimate snails ina slow manner.

I generally acclimate about 2 or 3 hours per 0.001 specific gravity unit. So for a change of 1.022 to 1.024, I would acclimate about 4 to 6 hours. A lot of animals can be acclimated more rapidly, but stressed snails can’t.

Sometimes you may receive snails shipped in wet newspaper. According to Dr. Ron, this is actually better for the snails. Here is what he has to say:

When animals are shipped they respire normally as long as their gills are wet. If they are immersed in sea water, and they have a reasonably high metabolic rate (snails, clams, crustaceans, many worms), they will rapidly exhaust the oxygen from the sea water and fill the sea water with carbon dioxide. This gas is exchanged at the water surface in the bag, mostly by diffusion and some by turbulence. This is a very slow way to replenish oxygen. Assuming some motion in the bag, this water will be partially mixed, but it will always be lower oxygen tension than is normal or optimal. Sometimes very much lower. This REALLY stresses the animal. Recovery at the end of this treatment is always somewhat iffy.

If the animals are kept moist in 100 percent humidity air, the gills are covered by a thin film of water, both carbon dioxide and oxygen can diffuse rapidly through this thin layer and the animals will survive a whole lot better than if kept submerged in water. The animals suffer no oxygen deficit and remain inactive as well. They basically just "wait it out." When put in water at the far end of the trip, they are ready to go...

I use to ship temperate marine inverts from one lab I worked at pretty much all over the US. I wrapped 'em in algae (kelp - lotsa mucus, keeps everything damp), then in damp newspaper, then into plastic bags. Most species could live a week or more under these conditions, and be fine at the far end.

(Both quotes are from: Turbo Snail Problems and Acclimatization)

The first group I’ll mention are the various Trochoidean snails/gastropods. Some of these include Turbo, Astraea (yes, I have that spelled correctly), Trochus, Stomatella, and Margarites. Most of these appear very similar, and are often difficult to differentiate between. Stomatella, however, are one in which the shell is quite different compared to the others. All of these snails graze on algaes, and most hobbyists that keep snails have had some of these in their tank at one time or another. The snails actually have differences in the “teeth”/radula. If you look closely at a snail grazing on your glass, then you can see how the snail moves its mouth scraping the radula on the surface. What I found interesting are the subtle differences in the radulae between species, which indicates differences in algae preferences.

Survival rate will depend on food availability. How do you know you aren’t dumping too many snails of one species into the tank?

My own experiences of this group, include a booming Trochus population. I witnessed a mass spawning event, continue to find small trochus, and watch them grow. My Astraeas, however, never do seem to live very long. Perhaps it is my acclimation technique, as from my reading it can take weeks sometimes for the effects. It very well could be shipping issues, as well.

 

[NaH2O]

Thought I would toss out some pics of a few from the first group: Trochoidean gastropods...

Astraea

Trochus

Stomatella

 

[kylem]

Hi guys,
I noticed you put a pic of the Stomatella snail in the last post....I found one last week in my sump and my brother found one in his. We couldn't find any info on these so I am glad I know the name of that snail now.
Is this a good snail or a bad snail?

 

[wrightme43]

stomatella is good. the little sundial looking one bad I hate those things. LOL Those stomatella are tough little guys. I was cleaning with my mag float and crushed the shell of one on accident. He bled and you could see where the shell had been broken. He has since recovered and has a little discolored place in the shell but otherwise just a cool as ever.

 

[Aly625]

my fav snail is the mexican turbo. it has an incredible ability to eat and eat and eat. you're only saposed to keep one per 20 gallons or they will starve. just thought that i would throw that in there.
-aly

 

[NaH2O]

Aly - Welcome to Reef Frontiers!!!

Kyle - Stomatellas are great additions, and will usually mulitply when more than one is present. A really cool thing about Stomatellas.....since they don't have the same kind of shape to their shell, they had to come up with a defense mechanism. "Traditional" snails have an operculum, or little circle door, that they can close on themselves when disturbed. Stomatellas can't retract into their shell, but they can break off a portion of their tail when disturbed. The broken part wiggles to distract the predator, while the rest of the body tries to get away.

 

[smalstuf]

I have a marine snail which is about 3/4 " long, black shelled, long siphon, something like turbellaria in shape. lays a clutch of 5-8 eggs. Does not touch macro algae, or harm coral.. Good with unicellular apparently, and great on detritus. Any idea what it is?

 

[LvFishguy]

I have found that astraea snails usually do very well in tanks the have hair algae in them. I put 6 of them in a clients 55 gallon tank about two years ago and four or five of them are still running to this day. I had originally put them in to control a hair algae bloom and they made short work of the algae and have since managed very well.

question about the shipping the snails damp. If you ship them w/o water and just keep them moist, how long do we need to accimate them?

 

[gobie]

Hey Good Topic, I Just Added The Following To My 75 Gal Reef, Not That Great Of A Price But I Figure A Good Mix Let. Me Know What You All Think
3 Trochus, 4 Nassarius, 5 Zebra Striped Turbos(these Guys Are Monsters),
1 Queen Conch, 3 Nerites, 3 Margaritas, 5 Ceriths, 2 Tiger Turbos, 10 Bumble Bees.

 

[reedman]

My questions on snails (and hermits and other cleanup crew members for that matter):

1) How do you determine appropriate stocking levels to avoid straving them to death?

2) Are they really as short lived as some sites would like you to beleive (6 months or so)? Based on comments above it seems to be a marketing ploy to sell more critters more often.

3) Once your tank is established and the algae bloom has died back, what are the best snails for keeping the glass clean and the detritus to a minimum.

At one point I bought $120 worth of snails and conchs from reeftopia (great place by the way). This was something on the order of 100 astreas, 50 Nassarius , 24 ceriths, and 2 fighting conchs (probably some others not related to this thread). I still have a few of the ceriths, but I beleive most of the rest have died off due to starvation. Some sites state that you need to refresh your clean up crews every 6 months to a year. Is this a true statement or do we just not have enough food source to sustain them in a healthy, mature tank?

Great topic Nikki!

 

[gobie]

you post a good question about how many how often. the bad thing I 've seen with astreas is once they fall from glass or rock they usually can't flip back over and die.
this would lead me to believe that is why they are so cheap. and adding 100 to any tank no wonder they died off they all starved.
let's face it algae is going to grow for some 2 times a year others, it never goes away.
so, it would seem that once catch up is done it's time to control the nutrients thus detritus eaters. that is why I went with a smaller more expensive mix rather than large lot of the same.

 

[NaH2O]

smalstuf - any chance of posting a picture? There are so many different kinds of snails, it is hard (for me anyway) to go off of description alone. The photo of the shell + a photo of the aperture/opening of the underside of the shell.

question about the shipping the snails damp. If you ship them w/o water and just keep them moist, how long do we need to accimate them?

I went to the article I linked in the first post on Acclimatization, and here is a quote from Ronald Shimek

They should be put directly into full strength sea water. If they were shipped from a normal locality their blood/hemolymph is at sea osmolality. This is the best way to ship them by the way.

Basically, what I read is the snails can osmoregulate. They will attempt to keep their blood at sea water osmalality. So, if they came from a tank where the salinity was lower than NSW, and they are shipped in the newspaper....the snails will lose excess water in order to make the concentration of their bodies more saline. If you keep your tank at a NSW salinity, then they probably don't need acclimation. However, if you don't, then I suppose you would acclimate them slowly.

Reed and gobie - let me do a little reading on the algae and I'll come back to that. In the articles I read, the food source seems to be an issue. Should we add so many snails that they eventually die off due to lack of food? Starvation sounds cruel, but is this what we are doing? I bought a gaggle of Astraea snails, and I have sufficient hair algae....however, they have been slowly dieing off. I did test the shipping water, and it tested for ammonia 0.3 ppm. I origianlly didn't think it was a big deal, but after the reading I have done, perhaps this is why my snails have lost their vigor. If signs can take weeks to manifest itself, then this makes sense to me. Oh, here is a thread on Clean-up Crew Bioload

 

[smalstuf]

:?:

I have a marine snail which is about 3/4 " long, black shelled, long siphon, something like turbellaria in shape. lays a clutch of 5-8 eggs. Does not touch macro algae, or harm coral.. Good with unicellular apparently, and great on detritus. Any idea what it is?

Did this topic tun off the wrong direction??? :evil:

 

[smalstuf]

Yes, I can try to get a photo and post it for these guys. I was supprized that all my snails made transport, and within a week had laid eggs. Its been about another week and you can see developement..so maybe the change in water or something spurred the rush to procreate. I just took 1/2 of them and reintroduced them into a tank with higher saline ( from 1.023 to 1.028) They seem normal.. hope they stay that way. I had fresh water tanks and snails in those things can be a menace, they lay so many eggs.. This will be interesting to watch.. If the young hatch and develope, I'll have about 200 fry. I could use some hair algae!

 

[gobie]

in reply to yourpost it could be a cerith snail but with out a picture it would be difficult at best to nail it down since there are so many species of marine tropical snails.

 

[NaH2O]

One snail that I noticed gobie has listed in his "snail list" is the margarita or sometimes referred to as margarite snail. This snail is often seen for sale, but may not be the best for a reef set-up. Again, quoting the article: The Grazing Snails, Part I - Turbo, Trochus, Astraea, and Kin

A large number of Trochoideans are sold to reef aquarists despite having little or no chance of long-term survival in a reef tank. Most of these are collected from the northern shores of Baja California. Although it's south of the United States, the marine environment of the northern part of this peninsula is anything but tropical. Its Pacific side is bathed in waters that are quite cool, and is the home of several Trochoideans that are collected for the reef aquarium hobby. These animals typically have a tolerance for warm conditions, and they are often intertidal animals and can withstand quite hot water - for a while. Prolonged exposure to warm conditions, however, kills them.

Among their many interesting attributes, many marine snails have impressively long life spans. I have counted over 120 annual growth rings on some specimens of Tegula funebralis, a temperate water species. This species is one of the three or four species of Trochoideans collected from cool water areas of Baja California and unethically sold to gullible, or informed, aquarists as a reef aquarium animal under the delightfully ambiguous name of "margarite or margarita snail. Tegula funebralis has a high thermal tolerance for an animal that lives in cold water areas (it ranges northward from Baja and is common in the British Columbian and Alaskan intertidal zones). They normally live a small fraction of one percent of their normal life span, or only a few months, in reef aquaria. Putting these animals in a reef aquarium is both unethical and immoral.

Reed - you have posed some great questions, and I'm not sure that I will be able to answer them. I can tell you what I have found, and perhaps we can figure out a good way to go about stocking a tank with snails. We know that snails have different numbers and shape of radular teeth, so they probably have differences in algae types/food, substrates to graze upon, or both. Key to keeping these critters long term will be in providing an adequate environment. I haven't been able to find information that says exactly what these requirements are. It was noted in the article that we are basically stuck with "trial and error". IMO, it is difficult to figure out how many you need, as one day you may be fine, and the next week have an algae outbreak that may limit itself anyway. We walk a fine line between too many nutrients, so one step too far, then we will need to dump more snails in to help clean up the mess.....only to end up starving them because the tank balances out, and excess nutrients are limited. I don't know that we would be able to "supplement feed" snails.....unless we can rent them to other local hobbyists. I must be doing something right with the Trochus snails in my tank. I see more and more baby trochus snails, and have been watching them grow.....I must have a great food source or else they wouldn't be propagating. Determining what that food source is, may be out of my grasp.

smalstuf - your question did not turn into the wrong direction at all. I'm sorry if you felt that way. The only thought I have in regards to your snail, is because of the "siphon" description, it makes me think of a type of Strombus snail. They have the proboscis/trunk. Is that what you mean by siphon? Hopefully, you will be able to get a pic. Also, were these snails purchased or hitchhikers?

 

[reedman]

I hear ya Nikki. I have hundreds if not thousands of these really small snails that come out in heards at night. They must be getting enough to eat or they would thin down. I learned the hard way that, while you can add large quantities to remove algae quickly, once the algae is gone and the nutrient import is under control you need to either offer up the snails to others that have an adaquet food source or watch them starve.

My observations so far:

Astreas are nice at first when you have lots of algae. After the initial bloom they seem to thin out quickly and are a pain because of their habit of flipping over without being able to right themselves.

Cerith are worth their weight in gold IMHO. They are good grazers on the rocks and do not get big enough to knock things over.

Trochus are good in smaller numbers. These seem to be hardier than most in my tank and do their job quite well. They do end up on every surface available (even ones that I can't figure out how they got there) so if you don't want a snail going somewhere...don't get these.

Stomatella are awesome. I have one of these that cruises around and it really is cool. Quite frankly, I don't care if it grazes or not, I just like watching it fly across the glass

Nassarius are great if you have a sand bed that you want to be turned over regularly. They are fun to watch when you put food in the tank. The sand will boil as they come to the surface.

 

[Stircrazy]

Nikki, just as a personal observation, I actually stopped drip acclimatizing my snails and have a better survival rate. Some reading I have done suggested that a snail can regulate the salinity levels on its own to create a gradual change (self acclimatization) kinda like what was mentioned about when you buy them in wet paper. I take them out of the bag they were shipped in for 5 min and them plunk them into the tank.. I am keeping about 90 to 95% of them now where be for with the drip I was only having about 80% live. I think is is due to the temp change when doing the drip.

I find astrea are awesome for smaller general algae and I use Mexican turbo's for hair algae.. I run the turbos at about 1 for every 8 gal with no problems. I would like to hear some info people have about trochus snails as they are pretty hard to get here but I hear they are worth the money.

Steve

 

[gobie]

update on shipment of snails for 75 gal reef. all snails were floating in sump 15+ min before I satarted to drip aclamate them. using my drip line from my calcium reactor (ca reactor is set up but not running co2 thru it right now) i punched a hole in bag with the barbed end of drip emitter and driped at one drop per sec. after 15 min i cliped open bag and removed 1/2 water and driped for another 10 min. kept bag open went on to next bag after 15 min with open I pulled out snails and released into main tank. repeated this 10 more times, and everthing looks good I havent lost a snail yet that I can tell.

 

[NaH2O]

Steve - that is interesting. I suppose taking them out of the water and letting them osmoregulate to sea water salinity isn't a bad idea. I wonder how long it takes them to get to that point - I never thought of testing the ship water for salinity. I will have to try that on my next batch. I have had issues keeping temperature when acclimating - I haven't been successful in somehow getting the container in the sump to keep temp, and where I can work with it.

I've had great success with Trochus snails....apparantly, whatever their food source is....I have it in abundance, as they propagate like crazy.

gobie - sounds like you have a good plan in place for acclimating. Let us know how they do.

I will provide info on to the next group of snails, hopefully during the weekend. It is holiday travel time for us, and I will need to escape once in a while.