A few weeks in, I'm already starting to regret getting a mantis shrimp

[wwarby]

I've had my peacock mantis shrimp for a few weeks now. I'd been fascinated with mantis shrimps for years and always wanted one as a pet, so dived straight in from no experience of fishkeeping at all. I've made plenty of beginner mistakes - most notably believing an LFS salesman who told me I could use bottled bacteria as an alternative to traditional tank cycling (my water quality tests proved that was a very bad idea and I'm still dealing with the results of that mistake), but my mantis shrimp is still alive and active.

I put two clown fish in the tank before the mantis arrived. I was warned not to do it, but I know at least one other reefer with clowns in his mantis tank that get left alone, and there are many other reefers with clubber mantis shrimps successfully coexisting with fish - though most seem to opt for faster and more aggressive species like the damsels or six line wrasse. I love clown fish though, so I figured it was worth a try to put my favourite fish in there since they're very cheap. It wasn't worth it. After a few days of peace, the mantis started terrorising them - chasing them around the tank repeatedly. It was horrible to watch and I took the clowns back to the LFS a couple of weeks ago.

I knew there was a pretty good chance I'd never be able to keep fish with the mantis, and that the mantis would spend most of her time in her burrow, but knowing and experiencing are two different things. For 5-15 minutes a day I've got the best pet in the world swimming around her tank, but the rest of the time it's an empty box full of wet rock, and my interest in it is fading fast. My intention was always to fill the tank with coral, but I'm pretty sure now that corals alone are not going to hold my interest.

Also I don't think I'm ever going to be at ease with the noise of her whacking the 8mm glass of my tank or (much more frequently) the inside of her PVC tubing burrow - which sound the same if you're not looking at the tank. It makes me nervous every time that she's going to break it one day. And it's possible the reason she's doing it is the 2 inch PVC tubing is too small for her (opinions vary on this). She certainly seems to be trying (unsuccessfully) to dig other caves for herself though.

I'm not sure what I want to do next, so the sensible thing is probably not to rush to a decision. My options seem to be:

1. Persevere, start adding corals and hope that over time my mantis shrimp becomes more active and visible
2. Try adding faster / more aggressive fish than clowns to give the tank some colour and interest
3. Sell or give away the mantis shrimp and re-stock with fish. This is where I'm leaning but it seems a weird outcome given I'd never had any interest in owning a reef tank except for the purpose of keeping a mantis. Also my 52 gallon tank is too small for most of the fish I'd really like to keep.
4. Cut my losses and sell everything

I know this hobby has a high attrition rate in the first year and I'm loathed to give up so quickly after I started, but if I'm this bored of my mostly empty tank already I think I need to change something quickly otherwise I'm definitely going to end up quitting.

 

[BroccoliFarmer]

I've had my peacock mantis shrimp for a few weeks now. I'd been fascinated with mantis shrimps for years and always wanted one as a pet, so dived straight in from no experience of fishkeeping at all. I've made plenty of beginner mistakes - most notably believing an LFS salesman who told me I could use bottled bacteria as an alternative to traditional tank cycling (my water quality tests proved that was a very bad idea and I'm still dealing with the results of that mistake), but my mantis shrimp is still alive and active.

I put two clown fish in the tank before the mantis arrived. I was warned not to do it, but I know at least one other reefer with clowns in his mantis tank that get left alone, and there are many other reefers with clubber mantis shrimps successfully coexisting with fish - though most seem to opt for faster and more aggressive species like the damsels or six line wrasse. I love clown fish though, so I figured it was worth a try to put my favourite fish in there since they're very cheap. It wasn't worth it. After a few days of peace, the mantis started terrorising them - chasing them around the tank repeatedly. It was horrible to watch and I took the clowns back to the LFS a couple of weeks ago.

I knew there was a pretty good chance I'd never be able to keep fish with the mantis, and that the mantis would spend most of her time in her burrow, but knowing and experiencing are two different things. For 5-15 minutes a day I've got the best pet in the world swimming around her tank, but the rest of the time it's an empty box full of wet rock, and my interest in it is fading fast. My intention was always to fill the tank with coral, but I'm pretty sure now that corals alone are not going to hold my interest.

Also I don't think I'm ever going to be at ease with the noise of her whacking the 8mm glass of my tank or (much more frequently) the inside of her PVC tubing burrow - which sound the same if you're not looking at the tank. It makes me nervous every time that she's going to break it one day. And it's possible the reason she's doing it is the 2 inch PVC tubing is too small for her (opinions vary on this). She certainly seems to be trying (unsuccessfully) to dig other caves for herself though.

I'm not sure what I want to do next, so the sensible thing is probably not to rush to a decision. My options seem to be:

1. Persevere, start adding corals and hope that over time my mantis shrimp becomes more active and visible
2. Try adding faster / more aggressive fish than clowns to give the tank some colour and interest
3. Sell or give away the mantis shrimp and re-stock with fish. This is where I'm leaning but it seems a weird outcome given I'd never had any interest in owning a reef tank except for the purpose of keeping a mantis. Also my 52 gallon tank is too small for most of the fish I'd really like to keep.
4. Cut my losses and sell everything

I know this hobby has a high attrition rate in the first year and I'm loathed to give up so quickly after I started, but if I'm this bored of my mostly empty tank already I think I need to change something quickly otherwise I'm definitely going to end up quitting.

Put the mantis shrimp up on classifieds, take the loss and start over with fish. We’ve ALL been there where are expectations are ultimately a let down in this hobby. Lemons or lemonade..your choice

 

[JGT]

Unload the shrimp. While this reefing hobby can be stressful at times to all of us, your sitch sounds like it might give you a heart attack. Not worth it.

 

[Lost in the Sauce]

My gut reaction would be to start looking at corals to hold your attention when the mantis is hiding, but given the system is fishless, not sure that's a great idea.

 

[wwarby]

My gut reaction would be to start looking at corals to hold your attention when the mantis is hiding, but given the system is fishless, not sure that's a great idea.

Yeah, my gut tells me I'm not going to be satisfied with just corals. They'll make the tank look pretty and I definitely feel like I'll go down the coral route if I stock the tank with fish, but I'm not convinced that tank containing only corals will be that much more interesting to me than a tank containing only rock.

If the mantis was out and about more frequently of the time I think I'd be happy, but I've literally seen her for about two minutes in the last three days. I could try some fast fish but the sensible options for tank mates seem pretty limited and I don't particularly like idea of just chucking more fish in there and hoping the mantis shrimp doesn't terrorise them.

Replacing the mantis shrimp with fish is probably the sensible thing to do. I'll spend a few days or weeks thinking about what I want to do though - I've rushed every decision I've made in this hobby, and it hasn't worked well for me so far.

 

[Cole.mormon]

Get fir of mantis +1

 

[Cell]

Best advice I can give is to start listening to advice given!

 

[Tired]

If you aren't enjoying the mantis, rehome it. Plenty of people love 'em. Though I think those people often have other tanks as well, so they have other things to look at.

Sometimes we try things that we've always wanted to try, and then learn that, in practice, it's not as cool as we expected. That's okay! Don't sunk-cost-fallacy yourself into keeping a tank you don't like.

Try a pistol shrimp/goby combo instead, maybe. Cool burrowing and symbiosis, with 99% less fish-terrorizing.

 

[Johnz]

Salt and Pepper Mantis Shrimp Recipe - Simple Chinese Food

in fact…… I struggled with this salt and pepper mantis shrimp, should I send it? why? Because of the salt and pepper method, someone will inevitably reply: The host must not be a coastal person, I really don't know how to taste it! Violent to the heavens! Hee hee, it's true that many people will...

simplechinesefood.com

 

[wwarby]

If you aren't enjoying the mantis, rehome it. Plenty of people love 'em. Though I think those people often have other tanks as well, so they have other things to look at.

Sometimes we try things that we've always wanted to try, and then learn that, in practice, it's not as cool as we expected. That's okay! Don't sunk-cost-fallacy yourself into keeping a tank you don't like.

Try a pistol shrimp/goby combo instead, maybe. Cool burrowing and symbiosis, with 99% less fish-terrorizing.

Yeah, that's good advice I think. I'd been talking about getting a mantis shrimp for 10 or 15 years before I eventually did it and I do love the mantis shrimp, I just don't like the empty tank when she's hiding and I hadn't really grappled with the reality of that outcome before I got started.

I definitely want to avoid trying to spend my way out of this funk. It's tempting to think I should get a smaller second tank for the shrimp and keep my current tank for fish, but I never really wanted fish in the first place and I'm not sure I do now. Replacing my mantis shrimp with fish in the existing tank won't be cheap (especially if I start buying corals too) and perhaps that's the real sunk cost problem - perhaps it's better to throw in the towel and chalk it up to experience.

 

[sfin52]

Yeah, that's good advice I think. I'd been talking about getting a mantis shrimp for 10 or 15 years before I eventually did it and I do love the mantis shrimp, I just don't like the empty tank when she's hiding and I hadn't really grappled with the reality of that outcome before I got started.

I definitely want to avoid trying to spend my way out of this funk. It's tempting to think I should get a smaller second tank for the shrimp and keep my current tank for fish, but I never really wanted fish in the first place and I'm not sure I do now. Replacing my mantis shrimp with fish in the existing tank won't be cheap (especially if I start buying corals too) and perhaps that's the real sunk cost problem - perhaps it's better to throw in the towel and chalk it up to experience.

You have a couple of options put mantis up for sale and rehome. Keep tank going with inverts and coral. Shrimp snails crabs and such.

Keep the mantis and add coral and hope it resolves your issues.

 

[motocross]

My mantis hasn't touched any of my fish. Granted I added them a few months after the mantis made its den. Speaking of I probably added 2 gallons worth of zip lock bags of rubble to keep him busy and not smashing everything all day and night to build said den. I have fish that swim right into its den all the time and to steal a few bites from its dinner. Corals on the other hand need to be secured well or it will move them where it wants which is usually upside down. Also, I've had two 6" peacocks and they both smash the glass here and there and never have the broken it.

If you really want to keep the Mantis I'd suggest a ton of rock rubble. This will stop it from trying to smash everything which it's probably doing to make some rubble for the den. Then it can rearrange everything. And it will regularly.

Feed every two to 3 days. One jumbo shrimp, med clam, and blue crab leg from the fish store will feed it for over a month.

Give that a few weeks, then add some mid to upper swimming fish.

I have a 40 breeder and it's plenty big enough for everything to coexist you should be able to pull this off. I even have 5 emerald crabs, 20 hermits, Halloween crab, snails, etc, that are surviving.

Some older pics to give you an idea of the amount of rubble I added and there's more on the other side and in the back. Still I plan on adding another 4 large handfuls.

Take your time and I bet you pull it off. Or not, lol. But at least you gave it an honest try.

After a few months

And today after idk a year or so.

 

[wwarby]

Thanks so much for the detailed response @motocross

I do have a fair amount of rock rubble in the tank Not as much as you - I have another pretty big bag full of it ready to but she's shown very little interest in the rubble I've given her so far. I gave her a pretty decent amount of waste pipe as a burrow with three entrances and that's her home - she does seem to make intermittent attempts to create a different home by burrowing, but gives up and returns to her tube burrow. Do you think adding loads more rubble would make her show interest in it, even if she's barely moved the 25 or so pieces I've already got in there?

I'm still finding my feet with feeding her, averaging one feed every 2-3 days, alternating between small frozen fish (about 1.5-2 inches long), cockles in shells and supermarket prawns. Everything I've given her she's greedily eaten so it doesn't seem as though the cause of my water quality issues is uneaten food (I see no trace of uneaten food anywhere) - I suspect my tank is just still cycling. Still I'm trying to limit food a bit now until the parameters are better.

Perhaps I need to do more experimenting with new tank mates. It's really hard though, some people like yourself have had plenty of success with tank mates, others just insist you absolutely cannot and should not put anything else in the tank with a predator like a mantis shrimp. It feels quite unethical putting other critters in the tank and just crossing my fingers they don't get killed, and I know I will be judged and criticised for doing so (probably rightly) by some forum members and LFS staff alike.

I don't need to make any immediate decisions, but I'm going to need to do something. I'm looking at the tank right now and I'm actively annoyed by the sight of it, because there's just nothing to see in there. Even a couple of fish would make a huge difference I think.

Do you have a view on whether the mantis shrimp will change her behaviour over the long run and become more active in the tank? One fellow reefer on ultimatereef.net says his mantis is out on view 80% of the day exploring her tank. I'm convinced she was out and about much more frequently when I had the clowns in there - perhaps she's just bored and there's nothing for her to see or do when she leaves the burrow so she's less interested now in coming out?

 

[Katrina71]

Have you considered posting him on here free to good home?

 

[wwarby]

Have you considered posting him on here free to good home?

Yeah. That's exactly what I'll end up doing if I decide to get rid. Here and/or ultimatereef.net anyway (I'm in England and that forum is specific to UK reefers). I don't want to rush to that decision though - I wanted a mantis shrimp for years and years and I was delighted with it when I finally got one, and I feel like I'd be happy if my tank just had a couple of fish in it or my mantis shrimp was more active. If I make the decision to get rid, I'll never get another one. I spent a lot of money and effort (for me) to get to this point so it's quite a big decision.

 

[Antyama]

Yeah. That's exactly what I'll end up doing if I decide to get rid. Here and/or ultimatereef.net anyway (I'm in England and that forum is specific to UK reefers). I don't want to rush to that decision though - I wanted a mantis shrimp for years and years and I was delighted with it when I finally got one, and I feel like I'd be happy if my tank just had a couple of fish in it or my mantis shrimp was more active. If I make the decision to get rid, I'll never get another one. I spent a lot of money and effort (for me) to get to this point so it's quite a big decision.

Has she molted already? I've read that for some, their mantis shrimp changed personality a lot, got bolder etc. after a molt. So you might want to wait at least for that and see if anything changes

Another thing, maybe add some Euphyllia or Pumping Xenia (yepp), I would reckon because they are highly visual animals, that having a lot of stuff moving would provide enough stimuli to explore. I plan on adding xenia to my mantis tank, because I want some movement and would be ok with it overgrowing everything

 

[wwarby]

Has she molted already? I've read that for some, their mantis shrimp changed personality a lot, got bolder etc. after a molt. So you might want to wait at least for that and see if anything changes

Another thing, maybe add some Euphyllia or Pumping Xenia (yepp), I would reckon because they are highly visual animals, that having a lot of stuff moving would provide enough stimuli to explore. I plan on adding xenia to my mantis tank, because I want some movement and would be ok with it overgrowing everything

Ah that's really useful information, thanks! No, she hasn't molted yet, so I think that's a good shout to wait for the molt and see if anything changes as you suggest.

What you say about corals also makes perfect sense. Looking at the tank, I can see why she wouldn't be that bothered about exploring - there's nothing at all going on in there for her to look at or interact with except bare rock and discarded pieces of cockle shell. Those two pieces of information I think might be enough to encourage me to persevere.

I need to get my water parameters under control before I even think about adding anything else into the tank, but then I think I'll at least try adding a couple of corals to see if it encourages her to be a little more active. I think maybe I'll also try just one new fish - a damsel or a six line wrasse as those two seem to be the likeliest to survive. I'll get a couple of snails and hermits too - just to see what she makes of them. I won't lose much sleep if she kills a couple of snails and crabs, and it'll give me more information about her appetite for murder.

 

[Antyama]

What you say about corals also makes perfect sense. Looking at the tank, I can see why she wouldn't be that bothered about exploring - there's nothing at all going on in there for her to look at or interact with except bare rock and discarded pieces of cockle shell. Those two pieces of information I think might be enough to encourage me to persevere.

I basically have the same setup for now, but my tank is near my pc, so my Shanks can always watch me and the screen haha.
I do think the molt might be your best bet, do note that it's not unusual for her to be reclusive afterwards, soft shell and all. Idk what you are feeding her, but it might also be a good idea to supplement frozen food with smth like Selcon. (I use AquaForest Garlic + Fish V since Selcon isn't available here).

They are intelligent creatures, so it's normal that they have a personality. It sucks but having to give it away because it doesn't bring you enough joy because it isn't as active, is absolutely valid and not shameful at all imo.

Bonus Video of my shanks running up to me

 

[motocross]

Thanks so much for the detailed response @motocross

I do have a fair amount of rock rubble in the tank Not as much as you - I have another pretty big bag full of it ready to but she's shown very little interest in the rubble I've given her so far. I gave her a pretty decent amount of waste pipe as a burrow with three entrances and that's her home - she does seem to make intermittent attempts to create a different home by burrowing, but gives up and returns to her tube burrow. Do you think adding loads more rubble would make her show interest in it, even if she's barely moved the 25 or so pieces I've already got in there?

I'm still finding my feet with feeding her, averaging one feed every 2-3 days, alternating between small frozen fish (about 1.5-2 inches long), cockles in shells and supermarket prawns. Everything I've given her she's greedily eaten so it doesn't seem as though the cause of my water quality issues is uneaten food (I see no trace of uneaten food anywhere) - I suspect my tank is just still cycling. Still I'm trying to limit food a bit now until the parameters are better.

Perhaps I need to do more experimenting with new tank mates. It's really hard though, some people like yourself have had plenty of success with tank mates, others just insist you absolutely cannot and should not put anything else in the tank with a predator like a mantis shrimp. It feels quite unethical putting other critters in the tank and just crossing my fingers they don't get killed, and I know I will be judged and criticised for doing so (probably rightly) by some forum members and LFS staff alike.

I don't need to make any immediate decisions, but I'm going to need to do something. I'm looking at the tank right now and I'm actively annoyed by the sight of it, because there's just nothing to see in there. Even a couple of fish would make a huge difference I think.

Do you have a view on whether the mantis shrimp will change her behaviour over the long run and become more active in the tank? One fellow reefer on ultimatereef.net says his mantis is out on view 80% of the day exploring her tank. I'm convinced she was out and about much more frequently when I had the clowns in there - perhaps she's just bored and there's nothing for her to see or do when she leaves the burrow so she's less interested now in coming out?

Id give it all the rubble and let him figure it out. If you really want fish then throw a few damsels in there. I doubt he will get them and if he does then hes doing you a favor cause they will torture most other fish.

As you see in my pics I made the mistake of using a white drain pipe, also with 3 entrances. He didn't like it and made a burrow right next to it. My understanding is they don't like multiple entrances so I put a large rock over the 3rd hole. Then he started to use the pipe more but still prefers the den he made.

How deep is your sand bed? I put about 2-3" of crushed coral for the top layer of a 6" sand bed to help his den keep some structure.

And although it's hard to see in the pics there's enough spacing between and behind my rocks for him to fit. The path is about 1" wider than he is and this was intentional. I'll draw a picture to give you an idea. It's going to look like a 3yo did it but hopefully it helps.

Idk about feeding a peacock fish. It's a smasher and usually eats crustaceans. Maybe you turned him onto fish and now he's a fish junky and can't help himself? Either way don't leave him hungry and he probably won't be interested in the fish. I'd try feeding him every day until he throws the food back at you. Then adjust to his appetite. Maybe you need to feed every day? Who knows but my approach was to stuff him to the point he's rejecting food and keep him there. I don't think they kill just to kill because I've watched mine carry a live hermit crab out of his den and toss it into the rubble.

They definitely change behavior. Mine used to sit in the den all the time. Now it comes out of the den looks at me and does a few laps around the path. Sometimes I find him on top of the rocks.

The way I saw/see it is, the shrimp was yanked out of its home in the ocean, put in a bag, and probably had to be netted and acclimated to multiple water parameters and tanks before it ever got to me. So I expected it to take some time for it to feel safe and I think as time goes on its realizing it's his tank and he's not going to be evicted. Hope this helps and post some pics of your setup so we can see what you have going on.


This is from the top down and only the base level. I stacked nice sized rocks on top of everything but you can see the path.

 

[motocross]

And I'd consider covering the tank for a week or so. This way he's in complete darkness and can molt of whatever. I intentionally bought a light that only covers half my tank and put it on the opposite side of his den and run it on the low side even if it means the corals don't grow as much as they should.

When you get this worked out you will be rewarded with an aquatic version of a pet dog that doesn't need to be walked. Hang in there everyone here will help get you squared away.