# Snail Population Booms/Causes and Cures



## chris oe

I've noticed we get questions over and over about snails from people who either have a sudden drastic overpopulation of snails in their tank, or who notice a snail in their tank for the first time and are concerned about the possibility of these snails "taking over" their tank. Its a common phenomenon, and one that is widely misunderstood in the community. I'd like to start a discussion on why this happens, how to control the situation once it occurs, how to avoid this kind of situation once you have snails present. 

I know people have particular snail eating fish that they like. I'd be interested in discussing the pros and cons of these fish, and pros and cons of the assassin snail. There's also the pros and cons of the "snail rid" type chemicals. 

There are also solutions that are snail tolerant, like managing nutrient level in the tank, being aware of the cycling and recycling of nutrition within the tank, and how that over nutrition sets a tank up for a snail boom. I'd like to see if we can work out an understanding of how that works in a variety of settings, and how to communicate with a new aquarium owner about how to get the situation under control. 

I am particularly bad about using weird imagery and giant words. I hope we could end up with something we could give to the average sophomore in high school, where they could read it, understand it, and implement it. 

I think its worth working on, because it gets at one of the cornerstones of what an aquarium is, how it works, and what is going wrong when things go wrong. If we can get people understanding this part, we've gone a far way towards getting them understanding what they most need to know to be successful at fish keeping.


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## James0816

Interesting topic for discussion.

We can start with introduction. Approximately 95% of all "pest" snail introductions are via hitchhiking in on plants. Depending on where you get your plants from, you're almost guaranteed to get snails. Even if there are no visible snails, their egg sacks remain. Being that they are clear jelly, they go practically undetected.

So what can you do? 

- First and foremost, always ask the seller if they have snails. Some will state this right off the bat but it's always good to ask so you don't get the surprises.
- Provide a PP (Pottasium Permanganate) for the plants when you get them. Dip the plants in this solution and it will kill all unwanted creatures.

Introducing fish to take care of a snail problem is usually not a good idea. This is due to the tank size that many of these require such as the Clown Loach. DP's (Dwarf Puffers) also love snails as a nice heartly snack. But, believe it or not, no matter how cute and small they are, they are actually vicious little buggers. Not recommended for a community tank.

There's a start.


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## lriecks1

What if you actually want to cultivate snails. What should be the chemistry and nutrient level of your tank.

Thanks


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## chris oe

What solution potassium permanganate do you use to sterilize your plants? How would you instruct someone on how to make it up so it is strong enough to kill snails and eggs and not so strong that it kills the plants? 

When I was fighting parasite infestation in my fish room I went so far as to break down all twelve tanks, bleach everything that could be bleached, throw out all the sponges from my sponge filters, and atttempted a potassium permanganate dip on all my plants, the idea being that a dip that was strong enough to kill snails would also kill any larval parasites and the intermediate hosts, which in that case were daphnia, but everywhere I looked online had different advice about the strength of the dip, or no specific strengths listed at all, and I ended up with a dip that was so strong it killed the leaves on some of my plants and turned my riccia to mush. 

What strength do you use, and what types of plants have you successfully used it on?


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## chris oe

What nutrients do you need if you want snails?

Most important would be a good carbonate hardness, so that growing young snails could put down a nice thick shell. Other than that it will depend on the snail species you want, and what its ideal conditions would be. Pomacea bridgesii (or are they diffusas now?) like good water with no ammonia, low nitrate and high carbonate hardness, for example. Not sure what a red ramshorn would like best, except that their shells are nicer with a good carbonate level and a good regular diet.


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## snail

I think it is worth mentioning for the sake of newbies that having snails in the tank is not the end of the world. Some snails can be a pest with some plants but most people object to them not because they they really do any harm but because they just don't like having them. If you don't like having snails you can poison them but they can add interest and clean algae and extra food. In most cases they will not explode in population if fish are not over fed and numbers can be kept low enough by squashing the ones you see if you wish.


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## chris oe

I personally love my snails, big and small. When we say snails aren't the end of the world, lets be clear: snails do not harm your tank. Most snails will not harm most live plants. Snails in and of themselves will not throw your tank out of balance. For the most part, snails that hatch out in your tank will not have been exposed to intermediate hosts, and therefor will not have parasites they can pass on to your fish, and most parasites and diseases don't even involve snails at all. 

A tank that is in balance will not have enough excess nutrients in it to support a snail population explosion. Snails cannot reproduce beyond what the available food in the tank allows, so if somebody suddenly has 50 adult snails in their tank it is because they had enough extra food or waste or algae or some other food to support 50 snails. If those snails weren't there, the food or waste or algae would still be, and there would still be a problem, it would just be an ammonia spike, or an algae bloom or something like that. Frankly, if I had to choose between an ammonia spike and a snail boom, I'd take the snails hands down. The ammonia spike could hurt my fish, while the snails won't.


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## James0816

chris oe said:


> What solution potassium permanganate do you use to sterilize your plants? How would you instruct someone on how to make it up so it is strong enough to kill snails and eggs and not so strong that it kills the plants?


I found the "recipe if you will" online. Stated to mix about a half bucket of water with PP until it is a dark purple color. Soak plants for about 20 minutes. Rinse well and then soak in a dechlorinator like Prime for several minutes. I haven't heard of any ill effects to plants like bleach. Most plants you can't soak the roots in bleach.


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## James0816

I'm the say way regarding them. I don't neccessarily mind them but do tolerate them. Bladder snails for some reason are a little more annoying than the pond snails (which I think are pretty kewl actually).


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## chris oe

James0816 said:


> I found the "recipe if you will" online. Stated to mix about a half bucket of water with PP until it is a dark purple color. Soak plants for about 20 minutes. Rinse well and then soak in a dechlorinator like Prime for several minutes. I haven't heard of any ill effects to plants like bleach. Most plants you can't soak the roots in bleach.


I keep wishing I could find something less subjective than color, but I think that is where I got into trouble, 'cause the recipe that I used did make use of measures, but that's the one that burned my plants. I suppose an amount small enough not to would be difficult to measure. Sigh.


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## James0816

I can do some more digging around in my notes to see if there was anything but I don't recall it. Everything I have ever seen was pretty much "mix to color".


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## slurik

Whenever i found that my tank was being overrun with snails I reduced feeding by 50%, snails slowly diminished in the week or 2 to follow this, clearly they thrive on liberated nutrition in your water. Also in conjunction with this, be aware that carbon will remove some small amounts of this nutrition your snails will thrive on, along with other impurities in your water also. Depending on if you do or dont fertilize, this may assist you a whole lot keeping the numbers down. Manual removal with lettuce leaves is just a lost cause IMHO.

As for getting them off of plants to avoid getting them into your tank truly requires an honest dealer, which are 1 in a million, and a chelated copper dosed in quarantine. Be mindful that coppersafe and other such products are absolutely deleterious to invertebrate life, as such this becomes a quarantine situation to remove hitch hikers, and will also require a nice rinsing before going into your display. Problem is that not everyone can quarantine plants due to lighting.

As for guy wanting to cultivate snails, they'll thrive on neglect and too much food. get a bucket and a crappy airstone, use a good lot of food, put it in indirect sun, and watch them explode in numbers. Good for puffer fish.


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## Gizmo

I have dealt with a pond snail outbreak. They do a good job of cleaning things, but they were in fact eating my plants. Bought two assassin snails which ended up making babies, and now 6 months later, all I ever see are a few egg pouches, and there are only three assassins left.

Assassins are great but you have to be ok with watching their numbers dwindle along with your snail outbreak as their food source disappears. Also, as stated, it took 6 months for the pond snails to be controlled.

I would have kept the pond snails as cleanup crew but people viewing my tank always asked about them rather than the tank, and some were even grossed out by the snails (why I don't know), in addition to the pond snails eating my plants.

Another way you can get snails is if a pet store clerk scoops some into the bag when getting your fish for you. This is solved by netting the fish out of the pet store bag instead of dumping fish and water into the tank together.


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## snail

[email protected] said:


> I have dealt with a pond snail outbreak. They do a good job of cleaning things, but they were in fact eating my plants. Bought two assassin snails which ended up making babies, and now 6 months later, all I ever see are a few egg pouches, and there are only three assassins left.
> 
> Assassins are great but you have to be ok with watching their numbers dwindle along with your snail outbreak as their food source disappears. Also, as stated, it took 6 months for the pond snails to be controlled.
> 
> I would have kept the pond snails as cleanup crew but people viewing my tank always asked about them rather than the tank, and some were even grossed out by the snails (why I don't know), in addition to the pond snails eating my plants.
> 
> Another way you can get snails is if a pet store clerk scoops some into the bag when getting your fish for you. This is solved by netting the fish out of the pet store bag instead of dumping fish and water into the tank together.


If you want snails that you don't see so much of try MTS. You can feed assassin snails food like bloodworms when there are no snails. As you say assassin snails are a very slow way of getting rid of other snails. They are often viewed more as a control than a cure. If you combine not overfeeding and squishing the snails you see with assassins it can work quite well.


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## Mac Myers

I always have a few Assassin Snails in the two tanks that I'm still adding animals to. Effective Control and they will decimate ramshorn, MTS, and pond snail populations in smaller tanks very quickly. They also breed SLOWLY. They can be expensive however. I get mine from a LFS for 2 bucks each.


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## chris oe

slurik said:


> As for guy wanting to cultivate snails, they'll thrive on neglect and too much food. get a bucket and a crappy airstone, use a good lot of food, put it in indirect sun, and watch them explode in numbers. Good for puffer fish.


That'll only work on some snails. Brigs/diffusas would either get up and leave the bucket or die. One way you can tell a tank has really gone round the bend is you find all the brigs on the floor around the tank. They're fine as long as they end up in clean water before they dry out entirely.


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## chris oe

The only problem with assassin snails, as I see it, is that they don't get at the basic reason why you have too many snails. Snails can't reproduce at a rate faster than there is food for them. If you don't have snails, you have snail food. So if you kill your snails, you're going to have what? Algae? Too much fish food? Maybe an ammonia spike? and then you still have snails, just carnivorous ones that don't eat your algae/fish food/whatever.


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## Gizmo

chris oe said:


> The only problem with assassin snails, as I see it, is that they don't get at the basic reason why you have too many snails. Snails can't reproduce at a rate faster than there is food for them. If you don't have snails, you have snail food. So if you kill your snails, you're going to have what? Algae? Too much fish food? Maybe an ammonia spike? and then you still have snails, just carnivorous ones that don't eat your algae/fish food/whatever.


I think the point of controlling/eradicating a snail outbreak is to free up the tank for some bottom dwellers you actually want in there, like shrimp or a pleco or some such.


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## chris oe

[email protected] said:


> I think the point of controlling/eradicating a snail outbreak is to free up the tank for some bottom dwellers you actually want in there, like shrimp or a pleco or some such.


Except that if you have such creatures, the surplus isn't there. Outcompeteing a baby snail is easy. Baby snails are incredibly slow, their range is small, and if they don't encounter sufficient food within their tiny range, they simply die. A shrimp or a pleco or whatever bottom feeder you have is going to do a much better job of finding food than a baby snail. The only way you have a snail population boom is if baby snails are finding sufficient food in great numbers, and that is proof of a surplus right there. If there is no surplus, it doesn't matter how many eggs the snails you have produce, the babies die. 

I have a 55 gallon with three different kinds of snails: diffusas, red ramshorns and mts. I also have three bristlenose plecos, and few if any surviving baby ramshorns or diffusas at all, though they lay plenty of eggs. I also have no carnivorous snails or snail eating fish and use no algaecides. Its because I have no surplus to speak of. I have a heavily planted tank, and I keep the nitrate level low, so there's not a lot of algae. I end up having to feed the bottom feeders algae tabs and such, and what I do feed gets rapidly eaten. Keep your tank lean and you will not have snail blooms. Keep your tank running a surplus and snails will be the least of your problems.


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## Mac Myers

I keep various types of shrimp. Some omnivores (and some Red Claw Macros that handle their own snail populations... as in there aren't any) but most are algae eaters. The tank lighting in those 3 tanks is set up to grow algae for the shrimp. Unfortunately it also provides food for a pest snail outbreak if I get some plants in and don't inspect them well enough. Assassins are pretty, control and/or eradicate populations, and will switch to eating shrimp food, flakes, or whatever whenever snails are scarce. Also, like MTS, they burrow through the substrate.
Plus the same LFS just sold me 3 more for a buck a piece an hour ago! I love the things. *w3


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## beaslbob

Every tank I have started (always planted) has had a snail bloom in the first few months.

Then a year later only 1/2 dozen or so are left.

So I just do nothing.

besides they to help clean the tank and are kinda interesting.


my .02


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## chris oe

I like snails. Pretty much haven't met a snail I didn't like with only one exception - I got given a pair of black snails (I don't know the species) that were the size of tennis balls, black shells, black bodies. They decided to chase the little common plecos I had, which was kind of funny (at the time) because the plecos kept trying to be leaves (I'm a leaf. Just ignore me, I'm a leaf.) then as soon as the snail would touch it, the pleco would take off. I built a couple rock caves for the plecos so they could hide out when the game stopped being fun. The next morning the caves were torn apart and there was nothing left of the plecos but the bony head plates. Needless to say I took those snails right to the pet shop and left them there with a warning. I never did find out what species they were. In MN there is a black viviparous snail native to the local lakes, could have been some of those, but I don't know. 

I like a peaceful tank where nobody is eating anybody, in general. That's just how I like it, though, everybody's got their thing.


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## snail

chris oe said:


> I like snails. Pretty much haven't met a snail I didn't like with only one exception - I got given a pair of black snails (I don't know the species) that were the size of tennis balls, black shells, black bodies.


Pomacea canaliculata prehaps? They are a large apple snail and are pretty destructive.


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## chris oe

Canalculatas? I've watched them lay waste to aquarium plants, but I've never seen one that aggressive toward fish. These were also almost twice the size I'd have expected a canalculata to reach, although when I look at Applesnail.net they do say canalculata max at 75 mm high - that's about right, but they don't mention black color variations. Hmmm. I imagine there's melanistic versions of just about everything. Woof. Yeah, I bet you're right, I bet these were huge, well fed canalculatas. All the more reason for me to stay away from canalculatas. They're the only thing I've ever seen that was able to eat live healthy java moss (which even goldfish can't eat). A good thing they're no longer legal in the aquarium trade. Invasive species? Yes, I bet they would be. Come right up to your back door and try to take off with your small yapping dog.


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## snail

Funnily enough I've seen my MTS eating Java moss. I knew something had been at it and couldn't believe it when I caught one in the act! It didn't cause much damage though.


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## chris oe

Really? MTS? Dang. Never seen mine do it, but then again, maybe I wouldn't notice. Little snails with tiny mouths eating tiny tiny leaves. Are you sure they weren't eating something off of the java, like maybe some hair algae or something?


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## snail

Nope, it was clearly stripping the leaves (there is probably a more technical name) off the stems as it went. It only happened for a month or so though and then stopped, even though I still have java moss and MTS in the tank.


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## chris oe

Funky. Learn something new about every 15 minutes or so ; )


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