The Planted Tank Forum banner

Assassin snails eat live shrimp!

108K views 47 replies 26 participants last post by  Khaleeka 
#1 ·
I know that there has been controversy on whether assassin snails eat shrimp or not. Well, I am here to tell you that they DO!:icon_cry: I received 8 assassin snails yesterday and I put them in my red cherry shrimp tank. This is a breeder tank and it has over 150 shrimp. I have just as much pond snails in there as well. I decided to try and reduce the pond snail population by adding some assassin snails. I put the assassin snails in the tank at 10pm and this morning there were 3 adult red cherry shrimp that were dead and one still being eaten. The night before all the shrimp were alive and healthy. I haven’t lost a shrimp in over 2 months so I know that they were all healthy. One assassin snail was still sucking out the meat of a red cherry shrimp :icon_evil. I just wanted everyone to know that if you have a high population of shrimp and you want to add assassin snails to your tank be prepared to loose some shrimp.
 
#2 ·
These are usually freak accidents. Your assassins must've been very hungry when you added them into the tank.
I'm a believer that assassins do/can/will eat shrimp when the opportunity is there. I was one of the first few people who experienced assassins eating their shrimp! I lost a blue pearl :-(
 
#9 ·
These are usually freak accidents. Your assassins must've been very hungry when you added them into the tank.
I'm a believer that assassins do/can/will eat shrimp when the opportunity is there. I was one of the first few people who experienced assassins eating their shrimp! I lost a blue pearl :-(
were there a lot of blue shrimp in the tank?
 
#3 ·
Were these wild caught or tank raised....?

I investigating these these further I am finding most case happen right after introduction and are wild caught snails. It means that they have gone for a long long period of time without being fed. Shrimp are native to their range so it makes sense that they would be on the menu, but tank raised are usually fed on a regular basis and are used to snails being easier prey, and more common than shrimp. I doubt that this will be an ongoing thing once they settle in. I have several tanks with 200+ shrimp and large amounts of assassins all tank raised with no shrimp kills.

Also pond/bladder snails are not high on the menu choices for assassins they prefer Ramshorns and MTS style snails. They will take the ponds/bladders down but usually when all other snails of eating size are gone or when they happen to just stumble on one and it is an easy catch. Bladders/ponds can both outrun an assassin.
 
#4 · (Edited)
The tank is a ten gallon and the shrimp are very dense in there. I can see why the assassins decided to go for the easiest meal (shrimp) since they were probably starving. The pond snails I am trying to reduce are the size of a BB, would the assassin snails be able to get at them? I have put some pond snails and blood worms in the new assassin snail tank just to get them by while I attain some MTS and Ramshorns.

The assassins were tank raised and they were only in the mail for 2 days.

Should I try and reintroduce them once they have been well fed?
 
#6 ·
Thanks for the info I will add it to my growing database of stats. I would say this is probably a case of easiest meal. I know my assassins feed daily and just because they were tank raised doesn't mean they got the right foods. I know a lot of people that feed their assassins blood worms and such but no live foods so first shot they get at live they jump on it.

If you can find out what the snails were eating at the sellers end that info would also be a big help.

I would say reintroduce, but if all you have are bladder/ponds that are that small then the assassins may not be looking at them as a food source. They usually like snails half as big to half again bigger than they are and leave the smaller snails alone either for the younger assassins or until they grow to eating size.

Again thanks for the detailed feedback.

Have you read this yet? Assassin Snails It explains all the details of Assassins that I have been able to gather and verify.
 
#11 ·
I have had that happen in a tank with no assassins. I lost like 5 in one night due to unknown factors and then the tanks were fine for 4 months then bam another small loss.
 
#15 ·
Somebody needs to tell my Cherry shrimp tank (20 gallon long) that they could be in trouble. I have at least two dozen Assassins in there.

http://i279.photobucket.com/albums/kk125/purgatori27/Shrimp Shots/100_2898.jpg
2 dozen that is all. I have 80 in one tank alone ... you'se got some catchin' up to do... The cherrys in there think the assassins make a nice feeding ground...:)

Yes Assassins will eat shrimp, but it is not a common or even an uncommon thing it is really rare. So I have a hard time swallowing that a whole colony was wiped out unless the snails were desperate for food since they had no snails to eat or you were not feeding them a high protien replacement food like bloodworms.

Most cases are wrong time wrong place, really dumb shrimp (which need to be taken out of the gene pool for stupidity anyway:icon_roll) or starved assassins. If you loss an entire colony it was because you starved the assassins or they were feeding on dying shrimp which is my first guess. I have kept assassin in large #'s with equally large #'s of shrimp and never had a recorded loss. I have also tried to recreate instances where an assassin would go after a shrimp and have not to this day been able to recreate it.

The main point with any predatory critter is to make sure that they have access to a healthy amount of their preferd food source. If that food source is not present then they will go after the next thing on the menu. I think this case is another case of hungry assassins eating on either already dead or dying shrimp or a case of first live prey they encountered and were starving.

Either way it has been added to my database and thanks again for the info bigshrimpin.
 
#14 ·
hey northsider, welcome to the forum. Its nice to have a north Chicago suburb represented. I am in Skokie and get to buffalo grove every now and then. If you are looking to trade anything let me know. I have a butt load of mini pellia with a slight staghorn problem I want to get rid of.
 
#18 ·
hey northsider, welcome to the forum. Its nice to have a north Chicago suburb represented. I am in Skokie and get to buffalo grove every now and then. If you are looking to trade anything let me know. I have a butt load of mini pellia with a slight staghorn problem I want to get rid of.[/quot

mini pellia, I have always wanted some of this stuff.
all I have is corkscrew val, duckweed, java moss, X-mas moss, and riccia. I have a buttload of cherryshrimp and am working on breeding more yellow, snowball, and minami dwarf shrimp. I just got some assassin snails as you know and want to see if I can breed these as well.

let me know if you want any of this and we can work something out.
 
#17 ·
We never thought you were lying just that there were some questions as there is in a lot of these cases and still are. So far I have only 15 or so of these reports that I find crediable and only one did the person actually see the capture itself. So you can see how those questions do come up. It was because of the open debate that your post started that had a lot of us trying to recreate it and got us looking deeper into the whole thing. So on that note we owe you a hearty thank you Ebichua...

So Thank You Ebichua...:thumbsup:

I never denied it could happen just that the cases were rare and actually because of yours and a couple of other reports that I found highly crediable I added that warning to my article.

On a side note I have come to believe that assassins have some kind of nero or paraylitic(sp?) toxin that would make it easier to caputre critters like shrimp and small fish. This belief comes from attacks I have seen and other reports from experienced keeper of how larger snails react after being attacked by assasins and then surviving. Some have shown signs at the point of attack of muscle deteroiation and also the amount of time required to recover is quite long. But I am no microbiologist just an highly motivated assassin snail freak....:)
 
#19 ·
@Bigshrimpin - any questions on breeding the assassins I will be glad to help I seem to have it down to a science and have about a 85% hatch rate and a 80% survival rate which is high from my studies.
 
#20 ·
Sounguru,
Thanks for the offer and I am going to have to take you up on it.
1. How active are your assassin snails?
2. I have a few that just hang out at the waters edge, is that normal?
3. I just put in 100 MTS, should I be supplement the assassin's diet with anything else?
4. The 10 gallon tank has only a sand bottom and a sponge filter, should I put some fake plants in there so they have a place to lay their eggs. I do not have enough light to support live plants in that tank.
 
#22 ·
I have large group Assassin Snails and RCS together in big tank. I don't find any problem.
After few months all pond snails gone, I start feeding all kind commercial food. The population's still growing. But one thing I observe, they get more reproduce when they eat live snails as compare they only eat commercial food.
 
#28 ·
After few months all pond snails gone, I start feeding all kind commercial food. The population's still growing. But one thing I observe, they get more reproduce when they eat live snails as compare they only eat commercial food.
I would also like to know what commercial foods your feeding them.
 
#23 ·
A thought just occurred to me...

I agree with the the reasoning that Assassins may eat healthy shrimp if they are very hungry upon arrival, or hungry in general. Then, there's always a chance you got a crazy one in there!

I do not think a happy, healthy NORMAL Assassin snail would harm a shrimp. Seems to me, they'd much rather be eating things that are normally on their menu and are easier to catch, plus they got other things to do...like mate, lay eggs, eat Ramshorn, and nap. I think there are always a few rogue ones out there (look at people, for instance once they get a taste for something).

It's very possible that you could limit the loss of shrimp being eaten by hungry, newly acquired snails by quarantining them a week or so. One of those "Ten Commandments" most of us don't follow. Of course, you'd be feeding them during quarantine (they love Ramshorn snails), so they may not be as likely to eat a shrimp after release. I guess they're gonna get protein one way or the other. Now, how much is it gonna cost ya?

I'm curious how many instances where a healthy shrimp is eaten, occur within the first month of snail introduction to the shrimp colony. I just want to know if placing them in a holding tank for a week or two and feeding them would decrease chances of attacks.

So, to be clear...I believe it happens...but why?
 
#26 ·
A thought just occurred to me...

I agree with the the reasoning that Assassins may eat healthy shrimp if they are very hungry upon arrival, or hungry in general. Then, there's always a chance you got a crazy one in there!

I do not think a happy, healthy NORMAL Assassin snail would harm a shrimp. Seems to me, they'd much rather be eating things that are normally on their menu and are easier to catch, plus they got other things to do...like mate, lay eggs, eat Ramshorn, and nap. I think there are always a few rogue ones out there (look at people, for instance once they get a taste for something).

It's very possible that you could limit the loss of shrimp being eaten by hungry, newly acquired snails by quarantining them a week or so. One of those "Ten Commandments" most of us don't follow. Of course, you'd be feeding them during quarantine (they love Ramshorn snails), so they may not be as likely to eat a shrimp after release. I guess they're gonna get protein one way or the other. Now, how much is it gonna cost ya?

I'm curious how many instances where a healthy shrimp is eaten, occur within the first month of snail introduction to the shrimp colony. I just want to know if placing them in a holding tank for a week or two and feeding them would decrease chances of attacks.

So, to be clear...I believe it happens...but why?
90+% have been within a few days of introduction from what I have been able to gather time line wise. And the few others have been when the pest snail population has dropped and they are not getting a good protien based replacement or stupid shrimp syndrome.... :icon_eek:

forgot to add the temp which is 78 just like yours.

what is plaster puck?
Parameters look good....

Plaster puck is a puck made out of DAP brand palster of paris and a very small amount of low fat fish food for flavor. The weekend and 7 day feeders you see in the store are basically the same idea I just make my own for pennies. They are nothing but a calcium block that disolves real slowly over time in which the pest snail will feed on to get more calcium in their diet. Which is then transfered to the assassins when they feed on the pest snails plus some disolves into the water column. Nice thing is I haven't had any PH increase using a puck where with Tums I have.

I have large group Assassin Snails and RCS together in big tank. I don't find any problem.
After few months all pond snails gone, I start feeding all kind commercial food. The population's still growing. But one thing I observe, they get more reproduce when they eat live snails as compare they only eat commercial food.
What are you feeding them exactly that info would be a big help since you are still seeing egg laying going on.
 
#29 ·
I am not speicify feed the snails alone, I just feed whatever (Tetras, ottos, shrimps and snails) they take.
Here's list:
Tetra fish flakes
Hikari Algae Waffers
Hikari Sinking Waffers
Hikari Carb Cuisine (first food they will pick, they love it)

I feed Waffers and Carb Cuisine couple times a week and flakes two times a day.

Temp 75 or above
ph 7.0 or below

I don't take much time to do maintaince.
25% WC once a week.

Note: sometime I saw they eat death fish.

Hope it can help !
 
#30 ·
Crab food is where they are getting most of their protien... Thanks for the info..
 
#31 ·
Interesting tid bit I found in a forum. It seems like this guy has experienced similar behavior. Some assassins like the water edge...
"Interesting about not having a lung Mel, they are in cycled tank and even when I was acclimating them in a bowl they all crawled to the surface for air just like brigs do. I even checked the water params which are rock solid just in case, I dropped the waterline as well. They all seem to enjoy poking their heads out for a bit and then plopping back into the water."
 
#32 ·
I know I'm jumping in here pretty late in the convo, but had to say our assassins are in two separate Dwarf Shrimp breeding tanks and we've not had any problems with them going after the shrimp. However the pond snail epidemic we were beginnig to have has cleared up splendidly!

Someone mentioned their assassins are in with their nerites!?! REALLY? We've got a collection of nerites, but avoided putting any of the assassins in those tanks. One because the PS problem isn't bad, two because we didn't want to loose any of the nerites....I'd like to hear more on that situation if possible.
 
#35 ·
Nerites are last on the assassin list and they are often ignored by assassins. Usually because of two factors.
A. Nerites are much bigger (except for clithon sp.) than assassins. So size deters assassins.
B. Nerites are stronger and have a trapdoor, making them more difficult prey.

However, if the assassin runs out of easy prey, they will go for nerites if desperate. Is it 100% safe? No, but it's not as likely for nerites to fall as victims than say, pond snails and rams.
 
#36 ·
Late to chime in but chicago folks, AA in schaumburg/hoffman estates has the assassins at 1/2 price.

I got 6 of them in a 52 as of 30 minutes ago, the new 4 have already eaten 3 MTS. I cant say if they eat shrimp or not because my angels take those out before the snails or anything else gets a chance.

My helena's take down large and same size MTS, they just crawl over the thousands of little MTS in the tank. they do not eat algae? mine do, or atleast they clean it off while moving thru the tank. I do like how they pack hunt too.
 
#37 ·
hey sorry for bringing up an old thread, but i just wanted to verify that they will eat shrimp. I had saw this thread and read part of it when I first bought my Asssassins, however keeping Amano's in the tank I figured I would be safe, they are fairly large, and I had only 5 of them. Along with the numerous amounts of pond snails, I figured that I would not have shrimp kills at all.

They proved me wrong, first day I put them in, I noticed them still eating a dead previously healthy Amano in the morning, and I noticed the snails another time all trying to seemingly corner another Amano, turns out they do eat big shrimp too.....
 
#38 ·
I'm just at a loss.

I had a colony of 9 cherry shrimp that were all happy and healthy. The tank had been stable for over a month except for a growing pond snail problem.

Added 3 smaller (3/4 inch) assassin snails a week ago and my shrimps have DISAPPEARED...i have a heavily planted tank, so I don't always see all of them, but I can usually find most of them.

a few days ago I could only find 5 after checking carefully. Today I can only find 2. strange thing is I don't see corpses or husks anywhere.

Any thoughts?

I have a 26 gallon planted tank with danios, swords and some small bumblebee gobies...nothing aggressive.
 
#39 ·
I've had danios eat my shrimps. They just pick them to death if the catch one out in the open. I literaly found this out yesterday. I had 5 small CRS an now I have only one. I only found one body, half eaten. Also the only fish in the tank are danios. Then danios were just donated to my LFS, and they gave me a few shrimps to re populate.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top