I thinks these worms are eating my snails, can you please confirm?

[professorjimjam]

Dear Friends!

Hope this message finds you in good health.

I have Malaysian trumpet snails (MTS) in my tank, which I have kept for more than two years. However, in the past seven months, I have noticed their shells deteriorating, as shown in the attached image.

This issue affects most of the snails, regardless of their size. My tank does not contain any pufferfish or other fish that might prey on snails. The only inhabitants are guppies and a pair of snow-white bristlenose plecos (one male and one female). There are no other creatures in the tank.

Several months ago, I introduced the worms shown in the second attached photo. I believe they are called blackworms. Their population has increased significantly. Despite siphoning and cleaning the tank, hundreds of them are removed, yet they seem to reappear rapidly. When I disturb the gravel during cleaning, I find many of them hiding underneath. Interestingly, the snails also remain under the gravel during the day and only surface at night to feed.

I strongly suspect that the blackworms might be causing the damage to the snails’ shells, but I could be wrong. The tank is clean, and all water parameters are optimal. I have even added a cuttlefish bone to ensure sufficient calcium levels, which remain stable and ideal.

I would greatly appreciate your help in identifying the cause of this issue. This problem is not limited to older snails, as even the younger ones exhibit the same shell deterioration as they grow. I do not believe it is a disease because, if it were, it would likely affect the other fish as well.

I am very fond of my snails and feel deeply upset to see them dying like this. They try their best to reproduce and create many offspring, but even the baby snails develop the same issue as they grow.

I have searched extensively for similar cases of MTS experiencing this problem but have found nothing.

Any help or advice would be greatly appreciated.

 

[FJB]

The worms are most likely not what is damaging the snails shells. The most likely culprit is low pH and soft water. The low pH results in thin, fragile shells that in turn causes shell dissolution and reduces the snails ability to incorporate additional carbonate towards shell repair.
The very fact that large populations of those worms are always in the tank is likely the result of excess organic material caused by insufficient maintenance, specifically removal of excess organics and water change. The excess organics also result in progressively lower pH. I could be wrong but I believe that is what is going on. Good luck.

 

[duanes]

I would tend to agree.
But 1st off...
What is the pH of your "tap" water?
Now compare it What is the average pH of your tank water before a water change?
What is pH after a water change
Can you test water hardness and alkalinity?

Or what does the water supplier list as its average parameters? (alkalinity, calcium hardness,general hardness)

MTS prefer pH above 7, and minimally moderate hardness.

 

[professorjimjam]

I would tend to agree.
But 1st off...
What is the pH of your "tap" water?
Now compare it What is the average pH of your tank water before a water change?
What is pH after a water change
Can you test water hardness and alkalinity?

Or what does the water supplier list as its average parameters? (alkalinity, calcium hardness,general hardness)

MTS prefer pH above 7, and minimally moderate hardness.

Thanks.

PH is tab water is 8 and after water change it is around 8 but before water change it is 7 and hardness is 17. the only issue is that i change water once in a month. the portion of water changed is 50%. Calcium I do not have tester, but i have the cuttlefish bone in the tank as well.

 

[duanes]

That 8 pH, should be fine for snails, but.
With only a 50% water change per month , my guess those are detritus worms.
Those should not be a threat to snails however, what ever is causing the snails to die makes great scavenging fodder for the worms to feast on.

Just curious, what are your average nitrate readings before, and after a water change?

 

[professorjimjam]

That 8 pH, should be fine for snails, but.
With only a 50% water change per month , my guess those are detritus worms.
Those should not be a threat to snails however, what ever is causing the snails to die makes great scavenging fodder for the worms to feast on.

Just curious, what are your average nitrate readings before, and after a water change?

Many thanks duanes

the nitrate reading before water change is getting around 17ppm and when I do water change it gets below 10ppm.

 

[FJB]

Just curious. How are you being able to measure nitrate at 17?

 

[professorjimjam]

Just curious. How are you being able to measure nitrate at 17?

I bought a liquid tester becuase the strap testers were completely useless. The JBL company have created very precise and effective water tester. It is a bit expensive but effective. I take 10 ml of the water and put in a container small bottle then as per instruction, I put a small tiny spoon of yellow powder then 6 drops of nitrate tester, then waiting for 10 minutes by then the water color changes , then I have a graph pamphlet which is guidebook for testing various aspects of the water. So the guide for nitrate has a color chart in that I take a photo from the bottle and then also take a photo from the guide color chart then asking chat gpt to match the color of tested water wiht the chart. Then it gives me the match and it shows in the range between 15 to 20 closer towards 15 arrow that indicates 17

 

[jjohnwm]

Do you find a lot of live snails exhibiting that same kind of shell erosion? Or do you just find empty shells that are dissolving away like that?

In any case, the worms aren't the culprits. That looks a lot like a tubifex worm in the pic, IMHO. If you have tubifex worms actually surviving and reproducing in your tank, that's a good indication that your substrate is, shall we say, less than clean. They live in the decaying organic matter at the bottom of usually stagnant polluted water; I collected them in vast numbers to feed my fish when I was a kid (a very messy enterprise), and rarely found them in water that could support most fish species. They were also sold in many aquarium stores back then, but I haven't seen live ones offered for a long while now.

Black worms are apparently different, I have no experience with them.

The critters that I grew up calling "detritus worms" are completely different again; much smaller, free-floating or swimming, whitish in colour. Nothing like what you show there. They are also normally seen in aquariums that are in need of more maintenance.

 

[professorjimjam]

Do you find a lot of live snails exhibiting that same kind of shell erosion? Or do you just find empty shells that are dissolving away like that?

In any case, the worms aren't the culprits. That looks a lot like a tubifex worm in the pic, IMHO. If you have tubifex worms actually surviving and reproducing in your tank, that's a good indication that your substrate is, shall we say, less than clean. They live in the decaying organic matter at the bottom of usually stagnant polluted water; I collected them in vast numbers to feed my fish when I was a kid (a very messy enterprise), and rarely found them in water that could support most fish species. They were also sold in many aquarium stores back then, but I haven't seen live ones offered for a long while now.

Black worms are apparently different, I have no experience with them.

The critters that I grew up calling "detritus worms" are completely different again; much smaller, free-floating or swimming, whitish in colour. Nothing like what you show there. They are also normally seen in aquariums that are in need of more maintenance.

Almost all of the MTS snails end up like that, but it does not start from the head of middle, it starts from the bottom of the snail. You can see I just picked up some young snails that are alive, but look at their bottom side, it shows it is broken as if someone is bitten the bottom of it.





here is another larger size, but look at the bottom side of it. the snail is alive, but losing the shell.




Now, I also have ramshorn snails , but this does not happen to them, here is a one of them, their shell even though more fragile than MTS, but still no problem. perhaps, it is because they do not dive in under gravel.

here is a photo.





Also, my Bristle nose couple, made around 40 babies, which are thriving in the same tank. not sure if these small plecos are eating the snails. but i doubt they would be able to eat the snails.
here is a photo. also, the MTS usually during night trying to climb to the walls of the aquarium.