Amphipod and cirolanid woes

[Tired]

I have a lot of amphipods. They're bothering my corals by walking on them. More concerning, they've been harassing one of my rock flower anemones into scrunching up, and then hanging out in the scrunched areas. They either made or worsened a small hole in its oral disk, even. I finally took the poor thing out, peeled off the (half a dozen) amphipods all over it, and currently have it floating in a cup so they can't get it. I'll... put it in something mesh, I guess. Breeder box for my poor harassed anemone. Can't keep it in the cup forever.

 

Now, normally I would fix the amphipod problem by adding a fish. Trouble is, I saw what I'm quite sure was a cirolanid isopod on November 16th. Definitely isopod-shaped, had the big eyes and everything. I caught the **** in a turkey baster, even! But I lingered slightly too long, checking that I'd slurked it up, and it swam back out. I assume it's still in here, unless it left on the rock that I took out. Not sure if those can be starved out at all, or if they'll just scavenge. It's sounding from my research like they don't starve out. 

 

So, how do I catch one or both of my problems?

 

I REALLY don't want to put an unprotected fish into this tank. That seems cruel, deliberately putting a (tiny, even) fish into a tank with a cirolanid. Like leaving your dog in your backyard when you know there's some kind of parasitic badger loose out there, leaving the poor thing to have a hole gnawed in its side. 

I'm going to be trying the method in this link http://www.reefkeeping.com/issues/2006-02/bp/index.php to catch the cirolanid, but I don't know that it'll work. I'm trying not to starve everything else that lives in here, so there's some food available. 

Does anyone know if cirolanids will chew through mesh? I thought about putting a fish in a mesh breeder box so its smell will work as bait, and waiting at night for the cirolanid to come and crawl on the mesh trying to get at it so I can get it. 

 

And on a potentially slightly easier trapping effort, how do I get the amphipods out? 

So far, I've tried a modified bottle trap. I made a bottle trap, but, as described in the link above, did it by drilling a hole in the lid. A couple of pods went in during the day, but went back out. I haven't tried it yet at night. 

Right now, I have some sorta-traps in the tank. I took some 2x2 squares of the sponge-mesh stuff that's around HOB filter cartridges, put some day-old (smelly) mysis on it, folded it up to render the mysis unreachable, and put the balls of mesh near dark spots in the rock. I'll try this at night, too. The hope is that the amphipods will burrow through the mesh to get the food, and will either become ensnared or (more likely) will decide to hang out in there so that I can yank the mesh out and bring them with it. 

What do amphipods like to hang out in? I'm hoping I can put something in the tank, wait all night, and then pull the whatever out and shake pods loose. Chaeto? Sponge? 

[Tamberav]

My mantis shrimp pets ate amphipods 🙂 I wonder if one of those would cure your problem. Would a isopod attach to a a mantis? 🤔

 

Sorry not what you asked for but thinking outside the box if you can't catch the isopod. 

[Tired]

I don't think cirolanids attack crustaceans in general. But I can't think of many suitable things that would work in here. It's a 4gal, I don't think the majority of mantis shrimp would work. Maybe one of those little not-even-two-inch ones, but those don't really get sold. And I do want fish, plus I have a pistol shrimp in here now, so I don't think even a tiny mantis would work.

 

Although there's a chance I have an extremely small mantis- something in here is making clicking noises from within the rock. Quieter than my 3/4" pistol shrimp, so whatever it is must be tiny, but something is making noises. How often do mantis shrimp make clicking noises? Is it just when they attack snails and whatnot, or do you hear tiny ones 'drilling' into rock sometimes? 

 

Out of curiosity, smasher or spearer mantises? 

[Tamberav]

Smasher, I would watch them smash amphipods. They will punch rock as well.

 

What about some fresh fish from a market? 

 

I have never had one of these guys but I guess I would try to bait it out. No idea how I have never had one as I add live rock, re-seed often and so on. 

[mcarroll]

WetWebMedia have anything on them?

[Tired]

Some. For cirolanids, they link to an article that advises using a bait fish to get them out, which I'm really not comfortable doing. Even if I could get a bigger fish in here. Though at least (on further reading) the kind I probably have is unlikely to be quite as awful to a fish as some species. Read: unlikely to BURROW INTO it. 

 

I'm going to try and trap both out tonight. I got some pastry bag tips (the little funnel things) and some tiny tupperware, and am going to combine them into, basically, a scaled-down bottle trap. I wonder if I might catch my mysterious clicking creature. Probably not, I assume it stays in the rockwork, but you never know. Hopefully I don't trap my intentional pistol shrimp. 

[mcarroll]

Sounds like a good plan. 

 

If you're trying to catch something that's attracted to the dark (ie a cave) make sure the trap looks like a dark cave too.  Use opaque plastics or maybe paint it black.  The opposite for a fish....as transparent as possible ought to be better.  (Not sure which category an isopod would fall into....don't know anything about how they see/how they target.

[Tired]

I'm going to be trying at night, so I'm not sure there's enough light for it to matter. They evidently hunt mostly by smell, anyway, so

 

 

okay, good, the cat has opted not to put all of her feet on top of the mesh lid of my aquarium. She got two of 'em on there, so I had some concerns. Guess she just wanted a smell of it. She used to like to sit on top of my 65gal freshwater tank and watch the fish through the glass lids... until I took the lids off during a water change, and she didn't realize and jumped up anyway. Yeah- she never jumped up there without looking VERY carefully after that. 

 

Anyway, I'll definitely consider the darkness thing, but I don't think I want to try and modify the container I have right now. I'll see what it catches. I'm going to pop a bit of sponge in there, in hopes that they'll go into the trap and burrow into the sponge without ever realizing that they're trapped. They're less likely to escape if they never notice and try. Just gotta keep 'em in there for a few hours- I don't want to leave this overnight, I don't want to suffocate whatever I catch. Partly because I might catch my pistol shrimp that I want to keep. 

[mcarroll]

I like it.  Keep us posted though!  

 

We're going hunting vicariously through you! 😉

[Tamberav]

I meant a dead (but fresh) fish. Does it HAVE to be alive?

 

I bought some live clams and live blue crab tonight... feeling pretty guilty about what I am about to do to them but I suppose someone has to be that guy if you eat meat.

[Tired]

Dead bait fish should work, hopefully, cirolanids will scavenge. The article suggested a live fish with a light color, so it's easy to see the isopods. Now, that would WORK, but I'd much rather use dead things if I can.

 

As to your seafood, clams aren't known to feel pain in any way. Crabs might, though. To be on the safe side, best to kill them before cooking. I know for lobster, you flip it over, place a sharp chef's knife lengthwise along it so that the tip is between the legs and the blade is over the head area, then slice down quick and fast to cut all the way through the head section. That way you cut through and instantly destroy the brain, which is about the most humane way to kill something. I'd imagine a similar method would work on crabs.

It's not as if they were ever going to die of old age- something was going to eat them. May as well be you. It's just best to kill them quickly. 

 

Edit: wasn't sure how clearly that was conveying anything. So, here's where you're supposed to cut on a lobster, and where I assume an equivalent cut would be on a crab. Maybe with the tip a little bit up more towards the 'head' that they don't really have. The main thing is to be sure you bring the knife quickly and strongly through the brain, and position it accordingly to make the cut easy. I've seen it done on cooking shows (though most of them unfortunately just boil things alive), and it works. Makes an awful crunching noise, but the lobster visibly goes from alive to dead right in that motion. It gets all limp, and then when they take it out of the pot after boiling, it isn't in that "trying to escape" backward-scooting position that a lot of the cooked ones are in at first.

[Tamberav]

Thanks! I will definitely kill it first like you showed. 

 

The clams are actually for my fish but the crabs are for me. :d

[Wingy]

I read about this on another forum.

 

Quote

The process is put piece of shrimp that has been sitting in salt water for 18+ hours (very stinky) in to a small bottle with string attached to the neck. Sink to the bottom of the tank and then its action time. The shrimp stays at the back of the bottle and the isopods swarm the bottle and hopefully find there way in too feed on the shrimp. I wait a few minutes and pull em up

The discussion went on to talk about needing to use a bottle with a narrow neck.  

[Tired]

That seems reasonable, and it's similar to what I'm going to try for that. I just have to get a very small bottle. Maybe one of those ones that hotels have alcohol in, in the minibars. I don't think a regular-sized bottle would even fit into this tank, with my rockwork the way it is.

 

For the amphipods, I was going to make some traps, buuut I found out that superglue doesn't work on Tupperware plastic. It's not that it dissolves it, it just doesn't stick. Gotta finangle the glue a bit for these. 

 

I also need to get a red light flashlight to watch them in the first place. 

[Wingy]

Anything thin and red will work to cover the end of the flashlight.   Use a red marker on a piece of clear plastic and cover it with tape to keep the color from coming off, a piece of red fabric, red areas on food packaging , there used to be a free phone app that turned the screen into a flashlight and you could change the color.  Look around and get creative.  As for superglue on tupperware, I think you need to rough up the surface for it to bond.  Try running it against a cheese grater.  

[Tired]

Guess I gotta find where we put that red Sharpie. I may just make a permanently red penlight-sized flashlight to keep by the tank. Really do need something other than my phone for this, because using your phone as a flashlight makes taking decent pics of weird bugs kinda hard. 

 

I got the glue to stick by using a LOT of it, and gel glue. It's not terribly secure, but it's viable. 

 

Last night, I tried messing with a bit of filter cartridge material until it was full of small holes, then rubber-banding that over a jar, in hopes that some would go in through the material and be hindered in fleeing when I pulled the jar out. I didn't get any takers on the mysis bait, I may need something meatier just to keep 'em after it. Partly since I think the bigger amphipods can actually carry mysis away. 

 

Today's agenda: big water change to clean out the nutrients from the rotting bait I used yesterday, fix some things in place with gel superglue so the fake-crabs will stop LIFTING them (turns out scarlet reef hermits use theri little claws like forklift arms to see what's underneath small flat things), rot some bait of some sort down for most of the day so it stinks as much as possible, and then try some traps tonight. Maybe clean out a tiny bottle, I think I have one somewhere.

Also, figure out how to keep this rock flower nem happy and separate, because the amphipods are bothering it real badly. If I wasn't trying to keep it alive, I'd use IT as bait. There's definitely a small hole in its oral disk, the cause of which I'm not sure. I wonder if the cirolanid got curious and took a bite. 

 

I'm mostly just hoping to thin out the amphipods, right now. I'd love to catch the cirolanid, but it's not a pressing issue. The amphipods are. Cirolanid would be amazing to catch, and that polyclad would be a lovely bonus, though that one's not an enormous concern. I'll see it again eventually, I hope, and it was pretty easy to catch the first time. Slow. 

[mcarroll]

Any idea why you have so many amphipods in the first place?  Has the tank gone through any big changes?

 

They aren't predatory by nature (not on anemones anyway....as far as I've read they are algae-eating detritavores) so it seems like there must be something driving their population to be so large that's it's creating starvation behavior and deviating them from their "normal" behavior.

 

Seems like if there was some algae and detritus in the tank that they'd leave the live critters alone.

 

The effects of diet mixing on consumer fitness: macroalgae, epiphytes, and animal matter as food for marine amphipods

[PDF link] http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.295.8249&rep=rep1&type=pdf

 

[Tired]

I don't think they're trying to eat the anemone, at least not mostly. They just seem to really like crawling on it. The two times I've removed it from the water to fish them off, there's half a dozen or more, and it won't unfurl when they're on it because they crawl all over it. It's expanded pretty well now that it's in a separate cup, though it keeps a bit of itself curled over the hole, I assume as protection. Since it scrunches up so heavily (further than it would normally for the night, even) with the amphipods on, and has largely unfurled now that they aren't on it, it seems to me that the amphipods must be what are causing it to retreat. 

My guess is, something else (the cirolanid? overly curious hermit? who knows) poked a tiny hole in the anemone, and they've chewed at that a bit out of curiosity. Mostly, I think they like to hide in the scrunched shapes it makes when it tries to retreat from them.

 

 

As to the population, I'm not sure exactly how many I'm supposed to have in the first place. Though I know they tend to overpopulate a bit in tanks with nothing to eat them. I think they multiplied during my initial hair algae surge, and then when I got snails to deal with that (and got sent way too many) and they ate all the algae, the amphipods got hungry. They definitely ate all the soft macros I had in here, all that's left is the calcified stuff. This is also a new tank, so population surges are reasonable, I'd just like to head this off a bit before they go after my zoas. 

My goal would be to keep them under control until I can get that cirolanid out. Then I can add a goby to snack on them. An antenna goby would eat the mid-sized and small ones, right? 

[mcarroll]

21 minutes ago, Tired said:

I think they multiplied during my initial hair algae surge, and then when I got snails to deal with that (and got sent way too many) and they ate all the algae, the amphipods got hungry. They definitely ate all the soft macros I had in here, all that's left is the calcified stuff

That makes perfect sense to me.  I'd hope this is a temporary problem in that case.

 

Wonder if those amphipods would gather on a piece of blanched lettuce (or other veggie...or even a wad of algae) placed in a dish in the tank so the whole mess could just be lifted out?  (Or even siphon them out.)

 

22 minutes ago, Tired said:

My goal would be to keep them under control until I can get that cirolanid out. Then I can add a goby to snack on them. An antenna goby would eat the mid-sized and small ones, right? 

The Hi-fin banded is pretty small....but seems like all fish like em that are big enough to eat em.   Could be borderline.  Plus he's not much of a hunter....might only go for the ones that come near.

 

What about a small damselfish or wrasse, and what if it was temporary?  (What size tank is it again?)

 

Do you really think a single isopod is that big a worry?  I've never had one, but why assume IT would eat the fish instead of vis versa? 

 

(And I don't mean that as rhetorical or to deter you.....just asking out of ignorance.)

 

 

[mcarroll]

Oh, I almost forgot.

 

Orkin Pest Control has a nice page on getting rid of Amphipods:

https://www.orkin.com/other/amphipods

 

🤣

[Tired]

Orkin has a page on getting rid of amphipods infesting your house and lawn. (Which isn't really an issue anyway, they die when it's too dry.) 

 

I considered a baby wrasse or damsel. The tank is a 4gal. I'm just not a fan of getting fish that I'm not going to be able to keep for their whole lives, plus I don't want to have to trap THAT out of my tank. Plus, I think a baby wrasse suitable for a tank this size would be too small to eat most of the pods, whereas a high-fin has a relatively large mouth compared to its body size. I also considered a clown goby- those have some pretty good teeth on them for their size. Or maybe a circus goby- nocturnal fish with a big mouth relative to its size. A bit on the larger size for this tank, but they don't seem to be a very active fish.

 

Cirolanid isopods are parasites. They specialize in approaching sleeping fish at night, quickly darting around to the side, and latching on. Sure, a fish might get lucky and eat it, but cirolanids are pretty good at avoiding that. Plus, this one is nearly 1/2" long, so I don't think any suitably-sized fish would be able to eat it. I'd also be worried about the cirolanid damaging the insides of anything that ate it. Maybe not outright escaping, but they've got little claws, a hard shell, and some form of biting mechanism, I don't want anything tiny to eat that.

[Wingy]

From my reading Cirolands will go after human flesh so in theory using a piece of supermarket fish should attract them. 

[Tired]

I'm not sure that human flesh and supermarket fish are equivalent, but I've read about people using shrimp that's been left to sit in some water for a few hours, if not overnight. The scent gets their attention. 

[Tamberav]

A molly would be easy to remove from the tank but idk what you would do it it. Return it after removing the isopod? 

 

As far as pods go....Greenbanded Gobies go for pretty large moving prey. I saw one of mine grab a nass snail and wrestle with it once. 

[mcarroll]

Fish are designed to eat stuff like that (see Pharyngeal_jaw)....anything they eat gets crunched up really good before it goes down.  Try feeding larger fish some larger sized pellet food and place your ear up to the tank and hear them grinding away on them.  It's kind of amazing in its way!

 

That said, I agree with you.....a 4 gallon is too limiting on what you could reasonably try, and 1/2" is too big for any of the fish we've mentioned so far....at least IMO.

 

I still have trouble visualizing a single individual isopod as a real threat, but I'm definitely no expert on them...not by any stretch.  (Way too rare....never even seen one in person.) 

 

Have you actually seen them jump a fish before??  (Trying to read up and even the literature says there isn't much literature on these things!  LOL)

 

What about using a cleaner fish or cleaner shrimps or even peppermint shrimps?  They're known to eat isopods when they're on a critter.....why not when they're off?   We know shrimp are active hunters and that if hungry they'll even rip apart a coral for food, so they're aggressive too.

 

In that same vein, you could introduce a target fish and then YOU act as the cleaner, removing it from the fish host.   You'd be doing nothing much different than what would happen in the wild....and the fish should be fine after.

 

Too many ideas now...hopefully that trap works!  🤣