Wayfarin
Arachnoknight
- Joined
- Mar 20, 2022
- Messages
- 237
Bladder snails.
Anyone who is considered an aquarium hobbyist has probably heard of them. Anyone with planted tanks has probably seen them.
They have lots of synonym names. Pond snails, tadpole snails, pouch snails, physae, etc. To pufferfish keepers, they are "feeder" snails. To most others, "pest" snail is the preferred term.
While many shrimp keepers and hobbyists love snails, they tend to lean towards nerite snails, trapdoor snails, and sometimes even red-rimmed melania snails, a sort of "loved and hated" species. These are the "good" snails.
Assassin snails are also "good" because they eat bladder snails.
Nerite and assassin snails? Good! Bladder snails? Pests!
But are bladder snails really pests?
Generally accused of being an invasive species, Physella acuta is probably native to much of North America. We're not sure how much of it's range is native, but it's probably native to the Mississippi River Drainage and most of eastern North America, perhaps ranging north to Maine and west to Montana. Many populations in North America may have originated in the Mississippi Drainage, been imported to the Old World, and then ended up back in North America, giving them a rather awkward status as "invasive" rather than native.
Wherever they came from, they are now common in the aquarium trade. Not intentionally, for the most part. The eggs and babies of this species are laid in aquatic plants, and those eggs and babies are hard to see, let alone remove.
In this respect, they are like red-rimmed melania snails. But unlike red-rimmed melania snails, these snails breathe air from the surface. This makes them extremely resilient to poor water conditions. They can even survive in tap water for extended periods.
This hardiness makes them difficult to kill.
But why kill them? Are they really that much of a problem?
It is indeed true that they are very prolific. A sexless species, one bladder snail can impregnate itself enough to lay multiple clutches of eggs. Once there are multiple snails, they mate with each other to produce even greater yields of offspring. I started out with one bladder snail. I now have several.
But what's even wrong with having an "infestation" of snails? Does it just look bad?
One problem they present is that they may clog filter systems. They have a reputation for doing this, but I can't find much evidence of this happening very often.
One of the most common ideas about bladder snails is that they pollute the aquarium with a high bioload of waste. But as far as I'm concerned, this is a MYTH.
Why? Bladder snails do indeed poop a lot, but because they dine on a mostly herbivorous diet, there is not much ammonia in their waste. What protein they do consume is often rotting dead organisms, which are nasty pollutants to water in their own right. In fact, almost all of what bladder snails consume adds some ammonia to the water!
. Dead plants
. Shed leaves and needles
. Dead shrimp and snails
. Dead algae (Much worse for water quality than living algae. In fact, algae is another organism with an almost undeserved reputation!)
. Uneaten fish food
. Fish waste (Some people say that they don't consume fish waste. While they probably do not consume significant quantities of it, it's very unlikely that they avoid it, since terrestrial gastropods regularly dine on dung.)
And what are they turning all of this into?
Waste.
Okay, so maybe they aren't "cleaning" the aquarium, but they are also barely adding anything to it.
And if your definition of bioload also refers to oxygen depletion, bladder snails barely breathe any oxygen from the water when they have access to surface air.
So they barely add ammonia to the water, and they barely use oxygen.
The same can be said for the similarly despised ramshorns, but cannot be said for the much loved nerite snails, which compete with shrimp and other tank mates for oxygen.
Okay, if bladder snails should die off for some cause, THAT would add quite some ammonia to the water. But the problem is the DEAD snails, not the live ones.
So assassin snails, another much loved species, aren't going to fix the problem. In fact, the bladder snails are more of a help to the problem that they cause, because live snails scavenge dead ones.
And because they are so bulletproof, it's actually quite unlikely that a die-off would occur. Such an problem would be much more likely for nerite snails, assassin snails, and shrimp, because they are so sensitive that many things can cause them to die off.
Bladder snails: 2
Nerite snails: 0
I'm not trying to degrade the much loved hobby snail species. But "good" snails and "pest" snails are just human labels, in my opinion.
And in my opinion, there is no such thing as a "pest" aquarium snail. Just a "hated" snail.
What do you think? Are bladder snails really the "pests" that people claim they are?
Share your experiences.
Anyone who is considered an aquarium hobbyist has probably heard of them. Anyone with planted tanks has probably seen them.
They have lots of synonym names. Pond snails, tadpole snails, pouch snails, physae, etc. To pufferfish keepers, they are "feeder" snails. To most others, "pest" snail is the preferred term.
While many shrimp keepers and hobbyists love snails, they tend to lean towards nerite snails, trapdoor snails, and sometimes even red-rimmed melania snails, a sort of "loved and hated" species. These are the "good" snails.
Assassin snails are also "good" because they eat bladder snails.
Nerite and assassin snails? Good! Bladder snails? Pests!
But are bladder snails really pests?
Generally accused of being an invasive species, Physella acuta is probably native to much of North America. We're not sure how much of it's range is native, but it's probably native to the Mississippi River Drainage and most of eastern North America, perhaps ranging north to Maine and west to Montana. Many populations in North America may have originated in the Mississippi Drainage, been imported to the Old World, and then ended up back in North America, giving them a rather awkward status as "invasive" rather than native.
Wherever they came from, they are now common in the aquarium trade. Not intentionally, for the most part. The eggs and babies of this species are laid in aquatic plants, and those eggs and babies are hard to see, let alone remove.
In this respect, they are like red-rimmed melania snails. But unlike red-rimmed melania snails, these snails breathe air from the surface. This makes them extremely resilient to poor water conditions. They can even survive in tap water for extended periods.
This hardiness makes them difficult to kill.
But why kill them? Are they really that much of a problem?
It is indeed true that they are very prolific. A sexless species, one bladder snail can impregnate itself enough to lay multiple clutches of eggs. Once there are multiple snails, they mate with each other to produce even greater yields of offspring. I started out with one bladder snail. I now have several.
But what's even wrong with having an "infestation" of snails? Does it just look bad?
One problem they present is that they may clog filter systems. They have a reputation for doing this, but I can't find much evidence of this happening very often.
One of the most common ideas about bladder snails is that they pollute the aquarium with a high bioload of waste. But as far as I'm concerned, this is a MYTH.
Why? Bladder snails do indeed poop a lot, but because they dine on a mostly herbivorous diet, there is not much ammonia in their waste. What protein they do consume is often rotting dead organisms, which are nasty pollutants to water in their own right. In fact, almost all of what bladder snails consume adds some ammonia to the water!
. Dead plants
. Shed leaves and needles
. Dead shrimp and snails
. Dead algae (Much worse for water quality than living algae. In fact, algae is another organism with an almost undeserved reputation!)
. Uneaten fish food
. Fish waste (Some people say that they don't consume fish waste. While they probably do not consume significant quantities of it, it's very unlikely that they avoid it, since terrestrial gastropods regularly dine on dung.)
And what are they turning all of this into?
Waste.
Okay, so maybe they aren't "cleaning" the aquarium, but they are also barely adding anything to it.
And if your definition of bioload also refers to oxygen depletion, bladder snails barely breathe any oxygen from the water when they have access to surface air.
So they barely add ammonia to the water, and they barely use oxygen.
The same can be said for the similarly despised ramshorns, but cannot be said for the much loved nerite snails, which compete with shrimp and other tank mates for oxygen.
Okay, if bladder snails should die off for some cause, THAT would add quite some ammonia to the water. But the problem is the DEAD snails, not the live ones.
So assassin snails, another much loved species, aren't going to fix the problem. In fact, the bladder snails are more of a help to the problem that they cause, because live snails scavenge dead ones.
And because they are so bulletproof, it's actually quite unlikely that a die-off would occur. Such an problem would be much more likely for nerite snails, assassin snails, and shrimp, because they are so sensitive that many things can cause them to die off.
Bladder snails: 2
Nerite snails: 0
I'm not trying to degrade the much loved hobby snail species. But "good" snails and "pest" snails are just human labels, in my opinion.
And in my opinion, there is no such thing as a "pest" aquarium snail. Just a "hated" snail.
What do you think? Are bladder snails really the "pests" that people claim they are?
Share your experiences.