# Amano Shrimp - hundreds



## summ3r (Jul 23, 2006)

My 12g tank has been invaded by baby amano shrimp. Hundreds of them. Not entirely sure how this happened - well ok, there was a mummy amano & a daddy amano... but everything I've read says that the baby shrimp need salt water to survive, and this is a freshwater tank so this shouldn't be happening. 

I've had amanos in this tank for years and was counting on the salt thing to stop any breeding because I really don't want the hassle. But there they are. 

There's a couple of generations of babies in there now, from some barely the size of a pinprick, to fairly substantial brutes of 1/16" who seem to be getting their extra protein by cannibalizing the smaller ones when they can catch them.

I've been taking care to not disturb the gravel and fishing them out of the bucket if any get sucked up during a water change but I really don't want to be taking care of babies. 

What on earth do I do with them? I want my tank back!


----------



## Fishyfishyfishy (Mar 3, 2008)

Interesting, but can't really tell if they are amano shrimp. Very anxious to hear see more pics when they get bigger!


----------



## Fishfur (Mar 4, 2012)

Those look like scuds to me. Not baby shrimp. I have a lot of scuds.. those look just like them. Amanos cannot survive to the shrimplet stage in fresh water, they must have brackish water for at least 30 days, and usually do not last beyond 4 days as zoeys in fresh water. So I'm guessing scuds and lots of 'em. 

Based on my somewhat limited experience with them, if you want them gone you are going to have to break down the tank and boil the substrate to get rid of them all. If you are seeing some of them 'riding' others on their backs, it's not cannibalization, it's breeding behaviour.


----------



## randy (Jan 29, 2012)

I don't think they are baby shrimps either, but kind of cute, aren't they? ;-)


----------



## default (May 28, 2011)

Not amanos sadly  but good live food lol


----------



## brapbrapboom (Sep 2, 2009)

Doesnt look like Amano's to me, maybe just put in a fish that munches on these little ones? 

Sent from my Galaxy Nexus using Tapatalk 2


----------



## bettaforu (Sep 6, 2009)

Nope not amanos at all, but SCUDS yes! 

Good luck with stopping them now...only way Ive cleaned my tanks of them is to drop a couple of very hungry Killifish in there for a few days....the Killies got fat and I got a clean tank 

I now round mine up by putting an algae wafer in a small container and leave it overnight, in the am I lift it out with the scuds still in there and pour it into my swordtail tank. live Breaky....thanks Mom.


----------



## prolific8 (Jan 10, 2013)

*scuds*

+++ to all replies that say they are scuds, they breed like rabbits, no wait even more so. And I have a hell of a time trying to keep them out of my tanks that do not have fish, even after full break downs and boiled substrate.

I am convinced they are guilty for deaths of freshly moulted shrimp, look into their natural habits and you will find that they are "programmed" to attack newly moulted females of similar crustacean species.


----------



## summ3r (Jul 23, 2006)

scuds, ok fair enough. I'd never heard of them before but in any case, how on earth did they get in the tank? I hadn't added anything new as far as I can recall. Makes a case for spontaneous generation. lol

Also, lots of room in the tank so I'll pick up some swords or killifish. I've never had a killifish. Can you suggest one that would fit into my tank and that would chow down on the scuds? 12g, currently holding 6 of the tiny gold tetras, 3 cardinal tetras 3 amanos and a couple of hundred scuds who are soon to be fish food.


----------



## bettaforu (Sep 6, 2009)

Mine were the bigger ones aka Golden Wonders...they sure made short work of the scuds and anything else that moved.

Bettas and Swordtails will hunt them down too. 

I wanted to clean my tank out of them so I put a small container in the bottom on the substrate and put a small algae wafer inside (there wasn't any other plants in the tank now) with the water lowered to just above the container, the scuds went looking for the food. 

In the next am I had a container filled with them, which I then took out careful to not lose any of the scuds and poured them into my swordtail tank....they were scattering everywhere hunting them down and munching on them. 

I just kept doing this each day until there weren't any left then I washed out the soil/tank and left the soil to dry out (which could be reused later on) no more scuds.

They come on plants that you buy/get and really can't avoid them, they are a sign that your tank is very healthy, because otherwise they would die off very fast. I have not seen them hunt down any shrimps or shrimplets myself, but they do outcompete for any food that contains vegetable matter like algae wafers.


----------



## iBetta (Jun 19, 2011)

so awesomeeeee (if you have my mindset). PERFECT reason to set up a new tank, and keep this one for live food if you have any other tanks with fish!


----------



## summ3r (Jul 23, 2006)

oh that's so funny! I can imagine the look on my dh's face when he comes back from his trip abroad and finds yet another tank! 

though, I have to admit - the idea does have a certain appeal!


----------



## Fishfur (Mar 4, 2012)

Scud is a somewhat derogatory nickname for creatures more properly known as amphipods, aka Gammarus. They are classed as detritivores, and feed primarily on algaes and dead plant matter. But they'll eat live plants if nothing else is available to them, and like most scavengers, including shrimp, will eat any dead critters they find. But in general, they are not known to attack creatures larger than themselves. Most species are found in salt water, the world over, but there are about a hundred species known to inhabit fresh water.

You most likely added them along with a plant, and because they cling with great determination to whatever they have hold of, you would not even have noticed them. You probably had them for quite some time before you ever saw one - though they are fast, they don't like light and are most active at night. They hide very well, in substrate, under dead leaves or other detritus, rocks or wood, and move along the bottom in little hops or bursts, going still and hiding between each move. Being popular prey items, they have a number of behaviours to help them avoid being preyed upon.

I first saw them after leaving new plants in a bucket overnight. When I removed the band at the bottom of the bunch, several little slender critters swam quickly away. Once I found out what they were, I debated awhile if I should keep or toss them. Ended up keeping them, and later on I discovered I already had them in both of my then existing tanks. They do a fairly amazing job of keeping algae off plant leaves.

Any I can catch now I slip into a dedicated scud tank, where I am trying to see if I can raise them for food. Though many of my fish are too small or too slow to catch such fast swimmers, or feed preferentially at the surface or at mid levels, not the bottom, I am fairly sure the loaches and corys eat them, because the tanks with those fish in them have the fewest scuds.

But in a shrimp only tank, they increase in numbers fairly quickly, and did the same once they got into my Q tank. While I never have seen a scud attack or eat a baby or moulting shrimp, that doesn't mean it hasn't happened. Can't keep an eye on every critter, every minute .

It would not surprise me in the least if they did prey on newly moulted shrimp, or newborn shrimp either, simply because they are scavengers, and most scavengers are opportunistic feeders, shrimp included. So if you want to raise dwarf shrimp, probably it would be best to keep their tank scud free if at all possible. Though once you get a few in a tank, getting rid of them is very difficult, unless you have something like Bettaforu's Killifish to hunt them down.

The tank I keep my scuds in is small, a 2.5 G, with no substrate, but plenty of java moss and a few chunks of lava rock, so they can hide if they want to. Currently it has a few juvie Amano shrimp in it too, but only 'til I get the replacement tank up for the one that cracked and leaked. They seem to ignore each other, and it's kind of fun to watch the scuds climb around the moss. When they mate, one rides another around like a rodeo cowboy, and even if they are netted, they won't let go of each other. Very determined, like I said .

I have learned that they are not the best indicator of high water quality, because they are more tolerant of degraded water than shrimp are. A few species are very sensitive to heavy metals and none can tolerate low oxygen water. But they are part of the large group known as macroinverts, which includes snails and many insect larvae too. Many macroinverts, including scuds, are collected to study water quality in rivers and streams.

Following are some sites with pictures or information about them, if anyone is interested in learning more.

http://www.fcps.edu/islandcreekes/ecology/scud.htm

http://insects.about.com/od/water-q...nitoring-Using-Aquatic-Macroinvertebrates.htm

http://www.maine.gov/dep/water/monitoring/biomonitoring/sampling/bugs/scuds.htm 
This site has a nice pic of one North American species.


----------



## randy (Jan 29, 2012)

Scuds do attack shrimps, mine do, at least smaller shrimps. I witnessed about 3 of these dang things clinched to a juvi fire red about 0.8cm, and the fire red was still swimming around trying to get rid of them. After a few minutes I could see the shrimp was losing the battle as he slowed down quite a bit. So I netted that shrimp out and put it in a feeding dish (3"x3" with 1" of water), scuds came off while I was netting. I knew it wouldn't make it as it laid on the side in the dish. Two days later when I remembered, I was ready to throw it away but found it alive and kicking, so it went back to the tank. I am unsure if it just molted when it was attacked, I'll have to find a way to get rid of these scuds.


----------



## Fishfur (Mar 4, 2012)

Since I only recently began keeping dwarf shrimp in shrimp only tanks, I have to admit that observing this kind of behaviour in the larger community tanks is, at best, difficult. 

So, Randy, I'm glad you posted that info. As I said, just because I haven't seen a scud go after shrimp myself, does not mean it doesn't happen. I am both pleased and disappointed to learn that this behaviour has been observed. Disappointed because it would have been nice not to have to be concerned, but pleased because now I know. I don't think it matters greatly whether the shrimp was moulting or not. If it was not, then all shrimp are at risk all the time. If it was moulting, then sub adult shrimp are in the greatest danger, because young shrimp moult far more often.

What annoys me is that because I was not particularly worried about scuds, I did not take particular care when I transferred plants from one tank to another. Thus I have transferred scuds with them, and now I have them in every tank. I am hoping there may be a way to, let's say, 'delete' them, from the shrimp tanks at least, so I've been thinking about that.

I have to start a new tank anyway, to replace the one that cracked. So first, new tank. Next, fresh substrate from a bag, not reused substrate. I think I'd thoroughly clean the old substrate, then leave it to dry out completely. Before I used it again, I think I'd boil it. If that doesn't do in any lurking scuds in old substrate, I'm not sure what would - perhaps soaking in bleach, peroxide or perhaps PP for awhile ? 

Then take cuttings of all the plants I'd like to use in the new tank, and soak them in a series of buckets, perhaps 3 or 4 of them over a period of a couple of weeks. If they're crypts or anything else with a crown and roots, I'd go for very small ones I could float for awhile. With any luck, any scuds on those plants are going to go to the bottom to hide at least during the lighted period. 

I'd have to make sure the plants did float, perhaps agitate them while the lights are on, to scare the scuds to the bottom. As they do seem to like algae tabs, I'd feed them tabs to lure them down too. Then transfer the plants to a fresh bucket 2 or 3 times, repeating the same procedure. Should get rid of most pond snails too. Hopefully all scuds that may have been on those plants will be gone before they go into the new tank, where I'd leave them to float awhile longer and observe for scud activity. In fact, now I think on it, if I put in substrate, they can use it to hide in. So skip the new substrate until I'm fairly certain the new tank is scud free. 

Bare bottom makes it easier to see if any scuds have made it into the tank, and if so, hopefully I could siphon them out fairly easily. Only once I was reasonably certain it was scud free would I add substrate, plant the plants, and transfer the shrimp. 

For now, I have to hope that scuds do not bother Ghost, Whisker or Fan shrimp, because 'deleting' scuds from the community tanks would be very, very difficult. At least in the community tanks, they are meals for the loaches and cories if nothing else, which helps control their numbers. For fish, they make a good food source, because they don't die and foul the water if not eaten quickly. 

I sure don't want any in a zoey tank either. I've only hatched Ghost larvae as yet. I observed that their newly morphed zoeys spend their time hanging just below the water surface for a few days, until they have moulted a few times. But once they've grown enough to walk and feed like adults, they head for the bottom, to graze on biofilm. At that point they're as vulnerable as any baby shrimp and they moult quite frequently. I would guess other larval shrimp might behave similarly. Fortunately, Whisker, Amano and Fan shrimp need brackish water to survive after hatching, so it would be nice if brackish water killed the type of scuds I have, then I'd have no worries for a brackish tank. 

Currently, I have a lot of Ghost shrimp but their eggs mostly end up as food for the Fan shrimp. But if I try to raise more I must make their growing tank scud free, 'cause I'm wondering now if scuds were the culprit behind the losses of very young Ghost shrimp I hatched last summer. Of those that morphed & reached approximately 3/8 inch in length, a large percentage vanished. At the time I thought perhaps their mothers were the culprits, because some of the mamas were quite hard to catch & remove after they dropped their eggs. But they were not in there long enough to account for all the losses, while scuds were present the whole time. 

If I succeed in eliminating scuds from my new tank I'll post it.


----------



## summ3r (Jul 23, 2006)

A follow up to my previous scud problem. Thanks to everyone for pointing out that it *was* a problem and not some new breed of hassle free amano shrimp! 
As soon as I found out what they were and how hard they were to get rid of I emptied out the tank and ripped it apart. Because they're crustaceans I washed the tank, every piece of equipment and every plant in a solution of snail killer. I dumped a pile of snail killer in the bucket holding the gravel and washed it. The water was black with scuds. It was really... ugh. And then I washed the gravel in snail killer a couple of more times. And left the bucket of gravel outside to freeze in the fresh March air. I thought, that'll get 'em. 
I used a pile of washed sand that I had on hand to make the new base, replanted, took 1/2 of the volume of water I needed from my 65g to make up the total, put the fish in and held my breath.
I didn't lose a single fish, even the crimson tetras were fine.
It's been 2 months and I haven't seen any scuds so far. I know they operate mostly at night so who knows. But I'm hopeful I've got it licked.


----------



## spanosilvio (Jan 4, 2008)

If it happen again to you, let me know, i wish my tank is full of scuds, i currently try to breed them, they are free food for my fish. 
I try to make them grow in my tank so they can feed on them when they want. 

Silvio


----------



## default (May 28, 2011)

Yea.. They're not really a problem... I have them in my display tanks under the foreground plants and they do a good job keeping the tank clean on the underside.
Usually see them doing the "deed" but they never get out of control in my tank. You just need some hungry fish and you got free fish food.


----------



## Fishfur (Mar 4, 2012)

Wish I'd known you were going to do that.. I'd have happily taken as many as you could scoop up off your hands.
Default is correct.. though I have them in all the tanks, those with bottom feeding fish, like loaches and cories, never have great numbers of them because they are eaten. Which is why I'm trying to culture them, as food.
They only get out of hand in tanks where they have no predators.. shrimp don't appear to eat them, though it may be they just don't eat enough to make a difference.


----------



## bettaforu (Sep 6, 2009)

I just stuck a couple of killiefish in my shrimp tank (after I had removed the shrimps) and next day not a one was left....my killiefish however had BIG bellies 

My sword tank does a good job of getting rid of them too, so anytime I want I bunch up all the floating plants and dump them on the surface of the swords tank....dinner is served. Then I just take the plants back out the next couple of days.


----------

