Some people are happy to have snails live in their tanks, especially Malayan Trumpet Snails (MTS) as they help clean up left over food and are good at turning over the substrate in planted tanks. On the other hand there are people who concider all Snails are pests and unfortunatly for the Snails I am one of them with the exception of Apple Snails which i used to breed some years back.
A few months ago when I was changing from my old tank to my new tank and I noticed a couple of MTS while removing the sand. I thought no more of this until I placed all the sand back into the new tank and filled it up. I came downstairs one night and put the light on in the living room and to my horror I saw hundreds of MTS climbing up the sides of the glass.
I have no idea how these Snails got into my tank, I do not use real plants or live food but they did. After searching the internet for how to remove them the best I came up with was to strip the tank and start again. I use CaribSea African Cichlid Complete Sand which is not cheap to replace so I found this to be an expensive solution. I tried all the other suggestions such as lettice traps and just removing the Snails by hand but nothing worked. Another option was to try some Assasin Snails. These hunt and kill all other Snails but unfortunatly I do not think that they would have survived amongst the cichlids. Due to the amount of MTS I was seeing i decided to take matters into my own hands.
I drained the new tank and removed all of the sand, luckily my fish were still in the old tank. I cleaned and dried the inside of the empty tank then set to work on the sand. Firstly I sieved through it all using a common household sieve. The holes were big enough to let the sand fall through but catch all of the big Snails, however it was possible for some of the tiny ones to fall through the sieve. MTS are live bearers so they produce live young.
I then boiled the sand pan by pan on the cooker for about 5 minutes each, drained it then left it to cool in a bucket. Once it had cooled down I placed it back in the tank and continued to set it up again.
One method I did try was clown loaches, I have kept them before many times with Malawi cichlids. It is said that they eat snails, well mine ignored them because MTS burie themselves down into the substrate and clown loach can not break their shells so i now have 2 clown loach playing with my cichlids.
UPDATE: Around 4 months passed and while doing a routine water change I found 2 very large adult MTS in the sand. The above may work for other Snails somehow the MTS managed to survive. Now I only had one solution, i had to strip my tank and start again. I removed all the sand and rocks so the tank had just water and fish, I left it like this for a couple of weeks so that I would see any Snails and remove them.
When I was happy that the tank was clear I placed my fish in a temporary home. This you can do by using a large but very clean dust bin or bucket lined with a black refuge/rubbish bag. Fill this with tank water and place a heater and airline in the bucket for aeration. Cover with a large towel and your fish will be fine in there for a few hours but remember to check them from time to time. I have used this method many times and never lost a fish.
Always save as much water from your tank as you can, I had 4 buckets plus the dustbin full. Once empty I wiped out the tank, did a small repair to the background then placed in the new CaribSea African Cichlid Complete Sand. During this time I had also stipped down the 2 external filters, cleaned them out and placed them and the media in a bucket of snail treatment called Esha Gastropex Aquatic Snail Treatment to soak along with the heaters, I also flushed out the pipes with boiling water. The crushed oyster shell that I use in the filters was replaced with new.
I then filled the tank with all the saved water plus some new conditioned water, set up one of the external filters and one heater then put the fish back and left them to settle, later on a replaced the second heater and filter. I did not put the lava rocks back in the tank, these had to be soaked in the Snail Treatment first. This will take a few days to complete but they will be replaced once they have all been treated.
As with any big water change or aquarium treatment, always keep an eye on the PH Levels, Temperature and water condition. Remember to always read the instructions on any snail treatment as it can be dangerous to use with some livestock.