Outbreaks of nuisance snails are one of the most common problems encountered in planted aquariums. Though much maligned, snails are perfectly normal in tanks with live plants and can even help with algae control. The problems occur when the snails reproduce and become out of control. Throughout our blog posts, we’ve gone over a number of methods of controlling snails through predators and removal methods, but as with any problems, the problem can be avoided with preventative measures.
A common way of cutting down snail populations is to dip new plants, killing snails and snail eggs before they enter your aquarium. We have here a few different “recipes” for these dips. Keep in mind that while these have been used successfully by many aquarists, sensitive plants may still be damaged. You can try your chosen method on one plant before using it on all of your new plants. These are also all solutions that are to be utilized in a separate bucket, tub or sink – NOT in the aquarium!
Just as salt will harm snails or slugs on land, it will dehydrate snails in the tank (and yes, even things underwater can be dehydrated!) Use aquarium salt or kosher salt to make a solution of one cup per gallon of water. Do not use table salt or iodized salt as they have other chemicals and preservatives not suitable for your aquarium or plants. Once all the salt is dissolved, rinse the plants in the saltwater for about 15-20 seconds, holding the roots above the water. After the saltwater rinse, rinse the plants again in fresh water before planting in the aquarium.
Alum (Aluminum sulfate) can be found in most grocery stores in the spice aisle. Dissolve 1-3 tablespoons per gallon of warm water and soak the plants for at least 2-3 hours, or up to 24 hours in milder solutions. It can be effective in removing snails, but is slightly less effective at getting rid of the eggs. As with the salt, rinse the plants in dechlorinated water before putting in the aquarium.
Not the powders or gels or Ultra Concentrated Colorsafe Stainbusters – just regular old chlorine bleach. This is one of the more severe solutions, but it can be very effective if used carefully. Since bleach can be harmful to some surfaces, it is a good idea to protect your work area and to wear gloves to protect your skin when using this method. Mix a solution of no stronger than 5% bleach (this translates to 1 part bleach to 19 parts water, or just over ¾ cups per gallon of water). Soak the plants in the solution for no more than 2 minutes for sensitive plants or 3 minutes for hardier ones, then submerge and rinse them very thoroughly in dechlorinated water. If the plants still have a bleach smell after rinsing, soak in water with dechlorinator before rinsing again.
Potassium Permanganate is a common ingredient in medications for parasites and bacterial infections. It can be found pet stores as well as in some hardware stores. A strong oxidizer, it is sold to remove iron from appliances like water softeners. It will react to any organic compounds – including your skin. Wear gloves and protect your work area against stains. Avoid using Potassium Permanganate around hydrogen peroxide, Formalin or any other substances containing formaldehyde or alcohols They can react and form a noxious gas.
Mix enough Potassium Permanganate with warm water to form a dark pink/purple solution. Since the concentration of the Potassium Permanganate varies depending on the source – aquarium medications, crystals from the hardware store, etc. – it is difficult to give a precise measurement for the solution. For most aquarium medications, it shoukd be about twice the recommended dosage of the medication. Soak the plants in the solution for 10-20 minutes before rinsing in fresh dechlorinated water. The dechlorinator will neutralize the Potassium Permanganate in much the same way it does the bleach. The well-rinsed plants will then be safe to plant in the aquarium.
Potassium Permanganate Solution image referenced from wikipedia and originally posted by Benjah-bmm27
Alum is way to go. Use 2.5 tbs per 1 gallon of water and soak plants for 12 hours if you’re intending to kill their eggs as well. Bleach kills everything, and PP is pretty nasty as well. If you decide to use either of these, consider lighting a match and burning everything in a 55 gallon drum instead. I’ve heard that alum has little negative effect on most, if not all, aquatic plants when rinsed clean and applied with care.
Trumpet snails are beneficial to plants. They aerate the substrate. If they’re cone shaped and resemble a Malaysian Trumpet Snail, strongly consider leaving them alone… In fact, don’t bother with any of them unless you’re trying to sell aquatic plants to ignorant customers that believe all snails are bad.
Hello Luke, Thanks for your comment. Every aquarist has different experiences and opinions on what works for them but all of these approaches certainly have their good and bad sides. The approaches here are rinses and dips rather than extended soaks like your Alum method and any method of getting rid of snails using a chemical can be risky with very sensitive plants.
I had a big problem with the Trumpet snail. My discus eat them and ended up heads down. I then had to put her in a sick tank with salt. Found lots of snails in her stomach, not good for them they are like cow gravers. Learned my lesson. I now and working on my other discus in the sick tank.
Lise: you found lots of snails in her stomach? How? Did you cut her open? Did she die from eating snails?? I’m surprised… I have small cichlids in with lots of Malaysian trumpet snails and never had issues with them eating the snails… But my fish tend to rip the snails out of their shells and eat the soft part only (When they catch them out of their shells just after lights on).
she was heads down and i had to put her in a sick tank with salt water. snails came out of her poo.. She then got better. No heads down which will kill your fish. tx.
It is not unheard of for fish like Discus to eat snails, especially if they are very tiny. They will usually crunch the shells but if they are small enough, fish can eat them which may cause an obstruction in their digestive tract and can cause problems. Not common but it can happen.
I used a pot perm dip a few weeks ago in my 55g. I lost all of my s. repens a beautiful carpet 3″ wide all the way down the tank, half of my crypts melted, my hygro pintafida and my pelia, my 4 true Siamese algae eaters and 3 angel fish died too. Weirdly I didn’t lose any otos who usually die if the wind blows wrong. Rinsing compulsively is recommended as the triple dose of prime didn’t seem to get it. I’m trying an alum dip tonight. I’m trying to get rid of some weird little round worm like critters and snails in my shrimp tank. I’m hoping it gets rid of snail eggs, I’ll try the 12 hrs and see. I moved the shrimp to a qt and I’m getting rid of the old substrate and putting in fresh eco-complete. I need to dip the nano filter and heater also if that will work. Does anyone know if it’s going to destroy my bacteria?
Hello Elizabeth, Did you treat the entire tank with the Potassium Permangenate or did you do the dip in a separate container? That is a pretty severe treatment as mentioned in this blog and would certainly be dangerous to the tank. The Alum treatment also should be in a separate container. Either of these treatments, mostly especially the Permangenate, will affect your bacteria. I would monitor your water conditions closely and make sure everything is stable before trying any other treatments or additives. Prime is a dechlorinator and water conditioner and shouldn’t have any effect on snail outbreaks. Carbon will help remove any traces of chemicals that may be left in the tank and adding livestock like some loaches or Assassin Snails can help control the snail outbreaks. I’m not sure what the worm-like critters you are referring to are but most organisms like that in freshwater tanks aren’t harmful as long as they aren’t on the fish themselves. If you are able to get a photo, you can email it to us at firstname.lastname@example.org and someone here can take a look at it for you and see if we can help you figure out what they are. If you would like to discuss your tank and the best course of action to get everything you have left healthy again.
Hey Eileen, lol nope I’m not an amature. I actually had 3 buckets set up. 1 with the permanganate and 1 with tap and 1 with prime. I think I did leave the plants and especially the Mopani and spiderwood in the pp too long. They may have absorbed too much pp. I have a ehiem canister filter that has carbon pads. Added 5 capfuls of prime directly to the tank when I put everything back. The next morning the water was milky and the 3 angels and SAEs were dead. Devastating 1 pair and the male of the other pair of marbled blues from AngelfishUSA, both proven breeders. I got the last angel out and put her in the QT she snapped out of it in seconds. The loaches and otos were unaffected. What I should have done is the 1-2 punch for algae. With that you add Hydrogen peroxide directly to the tank and then add all your filters, air stones and what ever to agitate the water. Do a 50% WC then add excel. It can all be done in the tank and did a wonderful job with the algae before. I thought I’d be “smart” and try something new. I should know better. I worked on my shrimp tank last night. It’s covered in snails and those weird round worms. The worms don’t seem to be a danger as much as unsightly. They aren’t planaria or hydra either. There’s no way to add loaches to get rid of the snails. I took all plants and the Mopani wood out and did the alum dip for about 4 hours at 4 tablespoons in 1 1/2 gallons. They are sitting in just tap water buckets with prime now. Some how I’ve got to catch the 30 or 40 Taiwanese fire red shrimp and put them in a QT, many of them are just born and nearly microscopic. Any idea how to do that would be appreciated. I’m thinking algae wafer in a shrimp net. Lastly I’m going to empty the tank and scrub it down and put fresh eco-complete in. At the moment I’m out of QTs once the shrimp are moved, so all plants and stuff are in buckets. I have no idea how long they can stay there. I looked everything over well and scraped off the eggs I saw. I don’t want to go through this again and I’ll NEVER use PP again.
Hi Elizabeth, It does sound like the permangenate soaked into the wood and caused the tank crash and that the plants may have just been dipped too long. The best bet now will be to re-establish the bacterial population of the tank. I would recommend switching from carbon to Chemi-Pure; in my experience, it does a much better job on heavy metals and chemicals than carbon and carbon pads. I think an algae wafer as “bait” in a shrimp net would be your best bet to catch your shrimp. If you are emptying the tank anyway, you can also drain the water level low to help catch them…just make sure you don’t siphon them up by accident in the process! If a loach isn’t feasible for you with your shrimp, you can try Assassin Snails. They are a more invert-friendly option to prey on the nuisance snails (and they’re pretty cute too).
No one has commented on the salt dip…?
And is “sea salt” equivalent to kosher/aquarium salt? I’d assume so but wanted to ask.
That would depend on what you are referring to as “sea salt”. You can check out the blog “What Is It and Why Do I Need it? – Freshwater Aquarium Salt” for more on the differences in types of salt. If by “sea salt”, you mean the type of salt used to make saltwater aquariums salty….yes, that is suitable as long as the plants are rinsed off in freshwater before being put into your tank. If you mean the “sea salt” sold in the seasoning section of the grocery store…maybe, maybe not. The important key here is making sure that the salt is NOT iodized or has any other preservatives, de-caking agents or other additives. The best salt to use for a salt dip to control snails is Freshwater Aquarium Salt.
Outstanding piece! It is well written and very educational. bravo zulu for your contribution!
Hello. I need some advice on how to proceed with a project of mine. I have a 29 tall filled with shrimp and a breeding pair BN plecos my husband added for QT a while ago. Well, the plecos LOVE the tank. It seems to be perfect for breeding. I now have sooooo many plecos and shrimp that I need to move them to a larger tank. I’m planning on moving everything over to a 45 long and add more plants. My plants in the 29 are also exploding with growth so they too need more room. I want to add more plant variety once I move everything, but am concerned with snails. We have had problems with massive snail population in the past. The tank is snail free and I would like to keep it that way. What would be the best method for pre-treating new plants to prevent snails that wont harm the shrimp as well?
Thank you for your time and advice
Hello Bridget, Pretreating the plants in a separate dip or bath using any of the methods listed in this blog will help eliminate the snails before the plants are added to your tank. As listed with all of those methods, just be sure to rinse the plants well before adding them to your tank.
has been a while since my heads down but she is doing very well and comes to me every morning to say hi blue. That his her name.she now has a half blind white discuss that I got. his name is snow ball. both are doing very well in helping each other out . as for my assassin sail they got rid of my other snails and have keep my tank in check now . seems like the assassin sail is not a small and do not grow as fast as trumpets do . no scary horror late night snail evasion with trumpet snails now all gone. :} makes me happy.
I recently set up a 10 gallon tank and stocked it with 4 neon tetras, 4 red minor tetras, an albino catfish and a small plant anchored in the gravel. The tank is pretty wide open and the tetras keep darting after each other. I ordered some anacharis and hornwort to add to the tank so the shy tetras have some cover, but I DON’T WANT SNAILS IN MY TANK!, so I also order some potassium permanganate to dip the plants in before I add them to the tank. After I dip the plants, I plan to keep them in dechlorinated water in an isolation tank before adding them to the main tank. How long should I keep the plants isolated so I can have confidence that all snails and eggs have been killed and will not invade the main tank? In other words, what is the gestation period for snail eggs?
Hi David, Snail eggs would usually hatch in about 2-4 weeks. The permanganate bath should kill them all but if you don’t see any new snails after 5 or 6 weeks, I would be pretty confident that you should stay snail-free. If you want to guarantee that you won’t have snails, you could use plants like the Tropica 1-2-Grow line instead of bunch plants grown in a nursery like Hormwort and Anacharis. These are the only plants that we carry that are guaranteed snail-free. We actually just started carrying them at our store and so far, our customers really like them. They are pretty small to start with but lot of the varieties are pretty fast-growing.
The population explosion of snails can also be controlled by not overfeeding your fish. That’s organic too!
Hi Audrey, Agreed! Preventing the problem is always the best way to eliminate it!
Ignore any advice that states “snails are helpful and don’t destroy them”. Even if beneficial, they reproduce like crazy and take over your tank (Malaysian trumpet snails included in that). Nerite snails will cover your glass in eggs and it takes a razor blade and lots of time to scrape them off. Trumpet snails and ramshorn will mass produce and it becomes a complete infestation that is so out of control that it’s hard to get rid of them all short of breaking tank down completely and throwing the gravel and all away and starting over. You can do traps or other rid methods but if you don’t stay on it constantly, eggs hatch and it begins again. I will never buy another plant that isn’t from tissue culture and I will never have another snail in any tank. There is no benefit worth it. Plenty of other things can give same benefits without being a pest.
I like the idea of having snails in a planted tank with dwarf puffers. I don’t have any now, but I am planning on a tank with that combo.
Hi Michelle, That’s a good plan for keeping well-fed puffers…just don’t keep any snails you are very attached to in with the puffers since they will get eaten.