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

[wwarby]

That's how people catch mantis shrimp normally. A 5-gallon bucket is absolutely fine for a few hours, though a pump or airstone would be a good idea. Preferably, give her a chunk of something to hide in while she's in there. No need for light, just for some amount of air circulation and for her to not be able to jump out.

Great. I have a spare mini pump that I use for mixing new saltwater so I can drop that in to create circulation, and a small piece of tubing or something for her to hide in. By "light" I just meant I wouldn't put a plastic lid on the bucket and leave her in total darkness - not that I thought it'd do any harm, just would then need to reintroduce ambient light gradually like when you open a shipping box. Anyway I have some netting I can use to cover the lid so she won't be able to jump out. Fingers crossed I can get the new burrow in there without too many adjustments to the rockwork before she starts a molt.

 

[Hadla]

Yeah she will be fine for a while in there! A pump and/or airstone helps also. You can always cover it with a light towel if you want, that’s what I do when I have something in a bucket for a while. Mainly to keep dust and other stuff out and whatever it is in! lol She sounds like an interesting girl!

 

[wwarby]

Can anyone provide a bit of context on what I Oatmeal might be trying to achieve with these rocks exactly? She's been shuffling them around for two or three days now, accumulating small piles in front of each entrance to her burrow, but she doesn't seem to be getting any closer to actually covering up any of the entrances, and sometimes she seems to get the rocks in pretty good positions to close up the gap only to undermine her efforts by pushing them away again.

Initially I worried that I might have given her too many big pieces and not enough smaller ones, and that may still be the case - but I'm pretty sure she's actually broken some of the bigger pieces into smaller ones (which is pretty impressive - I couldn't do that with my bare hands). There's also at least 15 chunks of rock scattered around the tank which are the same size or smaller than the ones I've seen her move, so I don't think it's an inability to move the other available pieces.

Does it just take them a long time to make their architectural plans? Or are the pieces I've provided not enough or the wrong size or shape? I could take some out and break them into smaller pieces, or give her a helping hand by moving some closer to the burrow entrances, or buy some live rock rubble with more angular shapes.

I don't actually really want her to finish this construction job before I get her new burrow in place, so I'm more just curious at the moment what exactly she's doing and how this process normally plays out. I suspect that the third entrance (pictured on the right side of the tank) is going to be really difficult for her to close up because of the way I've angled it upwards, so perhaps I should help her out and cover that one myself? I'm going to get rid of that entrance in the 3" upgrade to the burrow anyway.

Also if there's anything I should be doing about this green carpet covering my rocks I'm all ears. I'm gonna pop into the LFS today so I think I'll try my luck with some CUC. If Oatmeal eats them, it's not necessarily a bad thing as she'd probably benefit from the variety in her diet and the experience of hunting live prey.

 

[wwarby]

Update: I've just been to the LFS and added a bunch more rubble rock - a mix of live rock and dry rock rubble, with a few different shapes. If Oatmeal can't build a gate for her house with the building materials she has now, she's definitely not going to get that job at LEGO as a master builder

 

[Hadla]

Sometimes they just like to keep changing/moving things around and she might just have the piles ready for when she needs them to close up the tunnels. She looks/sounds like such a fun girl!

 

[Latte]

Yeah what Hadla said. My shrimp is constantly redecorating, it's probably very enriching for them to be able to interact with their environment like that which is great! More rock is probably going to be better so that's good too. I have a ton of little hermits/turbo snails in my mantis tank. I initially added them as live food, but my shrimp has never eaten any of them. Even when I pick up a hermit with tongs (how I feed her) and place it directly Infront of her burrow, she will just pick up the hermit and move it away from her burrow.

On adding fish, last night I acclimated some mollies to salt water and added them after a heavy day of feeding and four or so hours after lights out. All still alive this morning and doing well, so hopefully that trend continues.

 

[Latte]

For oatmeal, your best shot is likely CuC too small for her to bother with. Tons of copepods, limpets and the like (which should all be found on liverock) are probably your best bet. Worth trying some hermits and snails and you might get lucky too.

 

[vetteguy53081]

I caught my past one with a fish trap baited with a piece of shelled shrimp

 

[nmotz]

Thanks @nmotz, much appreciated. I'm very much still on the case with the water chemistry, but tested again today and things are still heading in the right direction with nitrites now down to about 0.025ppm - barely detectable on my test kit. Nitrates are still around 20ppm but my understanding is if nitrite has come down then nitrate will soon follow. Opinions do seem to vary greatly on how important the water chemistry is below a certain threshold but obviously I'll keep trying to get it lower. I feel like I ought to prioritise the burrow issue at the same time though - Oatmeal has been whacking the PVC for two days constantly now - she's clearly stressing about it.

Do you cap off one end of the U-shaped burrow? I've heard (can't remember it it was from you) that mantises don't really like burrows with multiple entrances so I feel like at minimum I should reduce the entrances from three to two, so discard everything right of the T junction. not sure though whether I should just cap off where the T junction is, leaving only one way in or out.

I'm thinking of going with 82mm outside diameter tubing which is 76mm on the internal diameter (exactly 3 inches). There are other sizes but I want to strike the right balance of making it big enough, but not so big she doesn't like it and not so big it's completely impossible to fit into my narrow tank and still have room around the aquascape to clean the glass. The only pipe sizes easily obtainable here in the UK are 32mm, 40mm and 110mm. Everything else is crazy hard to find and crazy expensive. Once I'm sure about the size and shape, I'll order the bits and do a trial run by placing a temporary new cave in the tank and see if she goes for it. If all is good then I'll take on the job of swapping it out permanently.

When you say that eventually she won't fit in the current burrow at all - are you saying she'll get even bigger than she already is? She's about 6-7" long already and I thought that was about as big as they get...

If Oatmeal is full grown then a 3” diameter pipe will be what you need. In the wild, Peacocks build a U-shaped burrow with two entrances. For that reason I don’t cap one end. Check my thread on this forum for some pictures. In your photos, I see algae on your rocks so that is a good sign that the chemistry is stabilizing somewhat and nitrates are being soaked up. Hope it continues!

 

[wwarby]

If Oatmeal is full grown then a 3” diameter pipe will be what you need. In the wild, Peacocks build a U-shaped burrow with two entrances. For that reason I don’t cap one end. Check my thread on this forum for some pictures. In your photos, I see algae on your rocks so that is a good sign that the chemistry is stabilizing somewhat and nitrates are being soaked up. Hope it continues!

Cool, that's good to know. The three inch pipe is on it's way so fingers crossed I can get it in before she molts. I've ordered the parts to make a 3" U shaped burrow with a somewhat elongated bottom (if that makes sense!)

Yeah the water chemistry is still heading in the right direction - I tested yesterday and it was slightly better than earlier in the week - nitrites and all but undetectable now. Nitrates still somewhere around 15-20ppm (I find it really hard to read colorimetric tests with absolute precision) and the algae is growing at pace now.

 

[wwarby]

Yeah what Hadla said. My shrimp is constantly redecorating, it's probably very enriching for them to be able to interact with their environment like that which is great! More rock is probably going to be better so that's good too. I have a ton of little hermits/turbo snails in my mantis tank. I initially added them as live food, but my shrimp has never eaten any of them. Even when I pick up a hermit with tongs (how I feed her) and place it directly Infront of her burrow, she will just pick up the hermit and move it away from her burrow.

On adding fish, last night I acclimated some mollies to salt water and added them after a heavy day of feeding and four or so hours after lights out. All still alive this morning and doing well, so hopefully that trend continues.

Thanks @Latte,

Yeah she's got loads of rock now it's fascinating watching her move the pieces around - it was definitely a good shout picking up more of it. It's curious that she never seemed interested in the rubble rock for the first few weeks and recently started handling it all the time. I still feel like she is preparing to molt (I've had her two months and I don't think she molted in the LFS for the couple of months they had her before I got her so she must not be far off due anyway). Perhaps she's not though, and she's just enjoying getting the pieces ready for when it's time.

As of this morning she's completely closed off one of the burrow entrances, but the other two are still open. I presume when it comes time for the molt she will close all of them?

 

[wwarby]

For oatmeal, your best shot is likely CuC too small for her to bother with. Tons of copepods, limpets and the like (which should all be found on liverock) are probably your best bet. Worth trying some hermits and snails and you might get lucky too.

Yeah I think I'm gonna try some CuC soon. At worst she eats them and it turns out to be an expensive meal that will be interesting for me to watch, at best it'll make my tank a little more interesting when she's in her burrow and help keep my algae under control. I'll do the copepods thing too - my LFS seemed to think it was a waste of time but I think this is one of those times when I should trust mantis owners over the LFS staff. They also seemed to think she'd kill any CuC, but your experience is direct proof that's not automatically true.

With regards to the copepods, the shops near me all seem to sell these sealed plastic bags of them (pictured below). They're about $2 each for 100ml. I've found branded alternatives in bottles online that all seem to be more expensive, but is there anything better about those? Otherwise I'm inclined to pick up a bunch of these cheap ones.

 

[wwarby]

Sometimes they just like to keep changing/moving things around and she might just have the piles ready for when she needs them to close up the tunnels. She looks/sounds like such a fun girl!

She really is fun to watch. Yesterday she was visible practically the whole day, moving her rocks about

 

[Latte]

She really is fun to watch. Yesterday she was visible practically the whole day, moving her rocks about

Definitely sounds like she's prepping to moult!

On the copepods, likely those $2 bags are fine. Inspect them and look for the pods, if there's a ton of active little bugs swimming around that shout be what you want! I couldn't tell you much more without taking a look under a microscope, but unless you want to fly me out from aus as a consultant, you'll have to trust the LFS on this one!

 

[Latte]

I don't understand though, they sell the pods but think they're useless? That explains $2 I guess!

 

[wwarby]

Well... I think she's molting now. She built a door over one of her cave entrances yesterday evening and I haven't seen or heard from her since. I've turned off the tank lights and left the lights off and the blinds drawn so despite the photo below looking like it's bright sunshine in her tank, that's just the phone camera being clever - it's actually almost pitch dark. I'm assuming the correct procedure now is no glass cleaning, no messing with the cannister filter, no food, no experimental clean-up crew, no light - basically just leave the filter and heater to do their thing and don't touch the tank at all until I see her again, and if that doesn't happen in a week or so, start testing for ammonia as that'll be the first sign she hasn't survived right?

I'm pretty nervous that I'm not gonna see her again - if @nmotz is right then she's gonna find it tough to molt in the 2" burrow, but there's nothing I can do about that now except cross my fingers and feel good about the fact that by the time she started the molt I had at least got my water chemistry pretty close to good. Wish me luck!

 

[wwarby]

I don't understand though, they sell the pods but think they're useless? That explains $2 I guess!

I think they sell them as fish food - they're not suggesting they're completely useless, he just seemed to think they wouldn't do anything particularly beneficial for the tank. I ordered some of these from eBay - I might pick some up from an LFS at some point too, but the guy I ordered from had taken the time to explain his breeding process in detail which I took as a good sign. Unfortunately I've already spent my Australian copepod consultancy budget for this month, so maybe next month for that

They'll arrive in water - is it safe to tip the delivery water into the tank? I don't have a sense of whether it's even possible to sieve the water with a fine net given how small they are.

 

[Latte]

Watch this! Pods pods pods

Can just dump the water in.

I really think Oatmeal will be fine! Best of luck, try not to stress too much.

I think they sell them as fish food - they're not suggesting they're completely useless, he just seemed to think they wouldn't do anything particularly beneficial for the tank. I ordered some of these from eBay - I might pick some up from an LFS at some point too, but the guy I ordered from had taken the time to explain his breeding process in detail which I took as a good sign. Unfortunately I've already spent my Australian copepod consultancy budget for this month, so maybe next month for that

They'll arrive in water - is it safe to tip the delivery water into the tank? I don't have a sense of whether it's even possible to sieve the water with a fine net given how small they are.

 

[wwarby]

Thanks @Latte, I watched the whole of that video - it'd actually been on my watch list for a while but at nearly the same length as a movie I'd been putting off watching it. Glad I did though very interesting

 

[wwarby]

I've been mulling over the idea of a moving Oatmeal to a smaller tank for the past couple of days. It's been suggested multiple times here and elsewhere. I've resisted on grounds of cost and not getting enough facetime with Oatmeal if she weren't next to my desk, but having thought more about where I'd actually put this tank and looking into costs, the idea is starting to seem more compelling. I'd be able to turn my 52 gallon tank into a full community reef tank which I'd probably get more enjoyment out of next to my desk whilst I'm working, and the mantis tank would live in my kitchen in a position where I could see it from my living room and dining table (it's an open plan layout) such that I could often notice she's out and about and go over to the tank to see what she's up to.

Before I run away with the idea I'd like to outline the plan and get some feedback...

I'd intend on going with the RedSea Max Nano 20g tank, which has an integrated rear sump, pump, skimmer, ReefLED 50 light and auto-topoff system. No cabinet, as it would sit on my kitchen counter. I'm working on the assumption that all of the equipment provided in the RedSea tank is adequate for a mantis shrimp and none of it would need to be replaced. The intention would be to eventually grow corals in the tank, but probably never add any fish.

That would leave me needing to buy a heater and Inkbird controller for it, sand, a mix of live rock and dry rock for the aquascape, a jump guard, magnetic scraper, backup thermometer, bottled bacteria and copepods (I'm listening to you @Latte!). All of the above should set me back less about £900, give or take. Would I need a wavemaker? If so, which one? Have I missed anything important?

I already have the 3" PVC on the way which I could repurpose into the new tank and build an aquascape around it. This time I'd obviously cycle the tank properly before rehousing Oatmeal, at which point I could restock my main tank with fish and corals.