Pyramidellidae snails – Tridacna killers – how to eradicate them

Tridacna Maxima

Tridacna Maxima

I unluckily had to solve the problem of the Pyramidellidae snails. They’re the plague that can weaken and kill the beautiful Tridacna clams.

Iquitos - mangimi tropicali - Colombo

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I didn’t know about the pyramidellidae snails, as well as the fact they could be the culprits of the damages to my Tridacna clams. I fortunately got aware of the problem soon.

I noticed that my Tridacna Maxima and my Tridacna Derasa didn’t open perfectly for some days. I observed them accurately and I saw this very little, white snails upon both the shells of my beloved bevalves. The snails were eating them!

In fact pyramidellidae snails usually feed themselves with the animal until they’ve killed it. They absolutely have to be identified in time.

How to recognize Pyramidellidae snails

They have few millimeters of lenght, white and tip-shaped. They’re very small so you have to inspect the Tridacna carefully to find them. Here below you can see the snails on the shell of my Tridacna.

Tridacna maxima con Lumache pyramidellidae

Tridacna maxima with pyramidellidae snails

In this picture you can see an enlargement.

Lumaca pyramidellidae sopra Tridacna maxima

Pyramidellidae snail

If they’re present, it’s necessary to remove them in time. I used some toothpicks, a pitcher and a bucket, and I removed them day after day from both the shell and the foot of the Tridacna. I eradicated all of the pyramidellidae snails, without leaving the bivalves with no water.

Thanks to a periodic inspection it’s definitely possible to get rid of this plague.

Natural predators

There are some fish that feed themselves on these snails.

The tail-spot wrasse or Halichoeres melanurus, it’s a natural killer of these parasites. Moreover it eats also the worst plagues of our tanks,  like planaria, turbellaria, ecc…

So it’s a good choice providing them even for prevention.

Halichoeres melanurus

Halichoeres melanurus

Another efficient option is the Halichoeres chrysus.

My Halichoeres melanurus (took exactly due to this  problem) immediately ate these parasites.

Curatives baths

I executed 4 baths with glucose in the aquarium water because my Tridacna were really weakened.

In fact Tridacna autonomously produce glucose in order to provide their needs. Curative baths allow us to give them their feed giving already the glucose ready for the osmosis. It’s a great help when the animal is weakened. Moreover it gives it more food in less time.

Tridacne in bagno curativo con glucosio

Tridacna in curative bath with glucose

The doses are: 1 coffee spoon of glucose every 2 litres of water.

You can find the glucose online on Ebay or Amazon, or in the supermarkets with a good cake department. The price is approximately 3 – 4 € for a 300 g can. You might use also the common sugar, but if you consider the ease of assimilation by the animal the glucose it’s better.

This cure revivified the animals and they already opened completely form the first bath. I executed 1 hour long baths every 2 days for 4 times, with a periodical inspect of surviving snails to eliminate.

Now I can say that (even though the fear of losing my Tridacna) it seems I totally got rid of them. Moreover they’ve completely rebuilt the byssus and reinforced.

I hope our guide can be useful to identify and eradicate these snails.