Mass snail die off, what happened?

[k8nabel]

Hi everyone,

I am curious to know if anyone has any insight for me as to why almost all of my pond snails and one mystery snail died within a few weeks of another. 
 

It’s a 30 gallon stocked with neon tetras, corys, and amano shrimp. I was experimenting with how long my water parameters would remain consistent without cleaning my canister filter, and with reducing my water changes to every other week. I continued to test the water twice weekly. It maintained with 0 ammonia, 0 nitrites, 40 nitrate (I have to dose easy green weekly to keep this up otherwise I drops to 20), pH is consistently 6.5, temp stays at 76-78, I have hard water with a GH at 150. These parameters have been relatively steady for the last year and all inhabitants healthy (aside for one bout of ick when the tank was new and has since been treated). 
 

Any idea what would have caused all of my snails to die? No harm done to shrimp, fish or plants. And nothing changed aside from not cleaning the canister filter and decreased water changes. I should also mention it’s is a very densely planted tank so I was trying to see how much work my plants are doing to maintain the water parameters. 
 

thank you in advance for any insight! 

[Zac]

On 5/29/2022 at 3:23 PM, k8nabel said:

Hi everyone,

I am curious to know if anyone has any insight for me as to why almost all of my pond snails and one mystery snail died within a few weeks of another. 
 

It’s a 30 gallon stocked with neon tetras, corys, and amano shrimp. I was experimenting with how long my water parameters would remain consistent without cleaning my canister filter, and with reducing my water changes to every other week. I continued to test the water twice weekly. It maintained with 0 ammonia, 0 nitrites, 40 nitrate (I have to dose easy green weekly to keep this up otherwise I drops to 20), pH is consistently 6.5, temp stays at 76-78, I have hard water with a GH at 150. These parameters have been relatively steady for the last year and all inhabitants healthy (aside for one bout of ick when the tank was new and has since been treated). 
 

Any idea what would have caused all of my snails to die? No harm done to shrimp, fish or plants. And nothing changed aside from not cleaning the canister filter and decreased water changes. I should also mention it’s is a very densely planted tank so I was trying to see how much work my plants are doing to maintain the water parameters. 
 

thank you in advance for any insight! 

My guess is either age or some fish we’re picking on them behind your back

[JerryP]

Snails are pretty good at announcing changes in your tank.  You are right to be concerned.  It could be that not cleaning your filter has caused a die off of the microscopic stuff the snails eat.  So they may have starved to death.  Are there still a bunch of snails in the tank?  They often bury themselves during the day and come out at night.  Too bad about the Mystery Snail.  They are interesting .  

[xXInkedPhoenixX]

Hi @k8nabel. I think @JerryP is onto something- they do tend to be a canary in a coalmine- meaning an indication of other issues. If your water parameters have been testing perfect there is something else that wasn't suiting their survival. Since the changes have to do with filter and water changes this could be a key. Maybe in less water changes minerals they need are not getting replenished. I would try adjusting one thing or the other (meaning either go to water changes or go to cleaning the filter) IF you have any snails left to see if there is a change in die off. 

I also have to say, I wouldn't replace the Mystery Snail- they require a higher pH (7s to 8.4) your water may be too acidic for them and will die sooner rather than later- I suspect that may be what could have caused the death there. (a quick google search says bladders prefer 7-8)

Edited May 30, 2022 by xXInkedPhoenixX

[Jennifer V]

Just another thought to throw out there, how often do you feed your fish, what amount and roughly how many bladder snails did you have in the tank before die off? It could be that there just wasn't enough food to sustain the population. Bladder snails can live in a wide variety of conditions, so I'm inclined to think your parameters are not the issue. 

The mystery snail death could be unrelated.  As @xXInkedPhoenixXmentioned, they do prefer higher pH so water parameters could be the cause there. 

[Guppysnail]

Along with what everyone else said this is the time of year water companies treat with all different types of things along with pesticides for farming that leech into the water systems. I would try increasing supplemental feeding as well.

[Chick-In-Of-TheSea]

On 5/30/2022 at 4:14 PM, xXInkedPhoenixX said:

the Mystery Snail- they require a higher pH

I agree with @xXInkedPhoenixX on the pH level.  They should have a pH above 7.  What type of diet do you give them?

Edited June 6, 2022 by Chick-In-Of-TheSea

[laritheloud]

I wouldn't jump to a problem right away if everything is testing fine. How old was your mystery snail/how long have you kept it? I have never had a single mystery snail live for longer than 7 months, sadly, and my water is highly alkaline at a pH of 8.0-8.2. I have decided to raise rabbit snails and Colombian Giant Ramshorns instead.

[BeeD]

Any chance they hatched at the same time? Was it only fully grown adults? I think young ones eat more, and I think I've had a couple die-offs due to the little ones upsetting the foraging balance. Or at least I think that was what happened because all of the little ones survived.

[nabokovfan87]

On 5/29/2022 at 12:23 PM, k8nabel said:

I continued to test the water twice weekly. It maintained with 0 ammonia, 0 nitrites, 40 nitrate (I have to dose easy green weekly to keep this up otherwise I drops to 20), pH is consistently 6.5, temp stays at 76-78, I have hard water with a GH at 150. These parameters have been relatively steady for the last year and all inhabitants healthy (aside for one bout of ick when the tank was new and has since been treated). 

With amanos in there, I'd keep an eye on KH as well.

On 6/6/2022 at 9:10 AM, Chick-In-Of-TheSea said:

I agree with @xXInkedPhoenixX on the pH level.  They should have a pH above 7.  What type of diet do you give them?

Agreed.  They also just might have run out of food, specifically calcium.  I would make sure once a week you're feeding Hikari Crab Cuisine (They have other versions as well for shrimp) so that your amanos and snails can get what they need.  Feed it a few hours after lights out.