A little over a week ago, my dad and I went out to a beach that's nearly always deserted. That's a relative rarity in this region this time of year, but it is a bit of a walk out to the best locations so I guess that must deter the sunbathers that clog up all the other beaches in the summer. I'd originally had the intent of grabbing a few of an invasive Grapsid crab species (for which my entire left side is covered in bruises...blasted algae-covered rocks), but there were also an awful lot of jellies that had moved into the area - enough that the water wasn't really worth wading into, since many were sea nettles that pack a rather nasty sting. I had a plastic scoop that worked really well to pick up jellies to look at them more closely, and you can probably guess what happened after the phrase "but wouldn't you like a jellyfish?" wandered into the conversation. So, here is the end result:
(Note, this a clickable image - it should take you to a video)
Please excuse the general mess around the glass bowl. I have some serious cleaning jobs to do around that tank.
The equipment is pretty basic: largest glass bowl I could find, an rather weak air pump, and a sponge filter hooked up by airline tubing. The sponge filter is not there so much to filter as it is to ensure flow without bubbles in the water column and protect the jelly from the intake via a sponge. I had it previously with just a bit of airline tubing, but bubbles in the water column can sometimes get trapped in jellyfish's bells. This happens to coastal ones a lot, and pretty much all the jellies I saw had this happen. They can usually fix it by just swimming upside down, so it's no big deal for them. Sometimes they eat the bubbles though, and their solution to that is a little icky. It apears they actually absorb the bubble into the bell itself as some sort of bubble cyst thing and then extrete it out the top of the bell. It leaves a little dimple that is gone the next day. I decided that was out of my comfort zone and that it is probably best to minimize potentially stressful events, so I went with a bubble-less water column that has let the jelly swim more freely since it's more like an open water environment than a rough tidal one.
Keeping water quality up has been pretty easy, by my standards anyway. Given that I have double-digets of tanks already, an extra small WC every 1-2 days depending on feeding has not been a burden. It's possible the sponge might start to cycle, but for the moment I've just been keeping up on the WCs and using a turkey baster to remove waste when I see it. I've been testing daily and haven't had any spikes to speak of yet since the bowl was set up. There was an initial small ammonia/nitrite spike a few hours after tank setup, but that hasn't repeated itself so I presume it was due to dieoff of what was in the small amount of actual sea water that got mixed in (since you can't exactly poor a jelly safely into a net to move it).
Right now I'm just feeding it live brine. I'm going to switch it to probably half live and half refridgerated plankton mix today though using a pipet to target feed and minimize waste. It goes through a frightening amount of live food that will have me making a lot of LFS trips if I don't switch it over, since I'm not set up to produce brine shrimp on the scale it wants currently with 2-3 feedings per day. At first it would periodically try to eat the glass and airline tubing, but it seems to have learned not to do that, which is pretty amazing given the absence of anything brain-like in these animals. The issue of getting caught on relatively smooth things like airline tubing seems to be a myth, at least with this species. I would imagine this is why the Norwalk Aquarium I posted pics of previously to is able to us mesh partitions successfully without having jellies plastered all over the mesh. Attempts to eat the airline tubing had me wondering if it had actually tangled itself (it was a knot of tentacles), but in literally a few seconds it can just let go of things, untangle, and swim away as though nothing happened.
I don't anticipate a huge, long-term success with this jelly, since among other things, this is a single adult that may be full grown and I don't know where it is in its life cycle. How long they stay in the medeussa stage is also up in the air; I've read anywhere from 2 months to 2 years for this species. Whether that's a lifespan in terms of time until killed by the environment/predators or time until some other natural death I don't know. So, this tank could last days or months, but regardless of how long I'm able to maintain this setup, it has already proven very educational and to me is therefore worth sharing.
If I do another one of these sorts of things in the future, from what I have seen so far I would probably go for a large plastic tub to be able to keep more than just a single jelly. One thing I don't like about the bowl is that there is no way to safely reach in there with a hand. Going in bare-handed would obviously be insane, and probably the jelly would try to eat gloves, which would risk me hurting it. More space would mean easier to reach in without snaging a jelly, and operating purely with tongs and turkey basters can be a bit tricky with a narrow opening at the top. A larger/wider setup would also allow for mesh partitions to have more equipment (perhaps some LR to decrease the need for WCs).
(Note, this a clickable image - it should take you to a video)
Please excuse the general mess around the glass bowl. I have some serious cleaning jobs to do around that tank.
The equipment is pretty basic: largest glass bowl I could find, an rather weak air pump, and a sponge filter hooked up by airline tubing. The sponge filter is not there so much to filter as it is to ensure flow without bubbles in the water column and protect the jelly from the intake via a sponge. I had it previously with just a bit of airline tubing, but bubbles in the water column can sometimes get trapped in jellyfish's bells. This happens to coastal ones a lot, and pretty much all the jellies I saw had this happen. They can usually fix it by just swimming upside down, so it's no big deal for them. Sometimes they eat the bubbles though, and their solution to that is a little icky. It apears they actually absorb the bubble into the bell itself as some sort of bubble cyst thing and then extrete it out the top of the bell. It leaves a little dimple that is gone the next day. I decided that was out of my comfort zone and that it is probably best to minimize potentially stressful events, so I went with a bubble-less water column that has let the jelly swim more freely since it's more like an open water environment than a rough tidal one.
Keeping water quality up has been pretty easy, by my standards anyway. Given that I have double-digets of tanks already, an extra small WC every 1-2 days depending on feeding has not been a burden. It's possible the sponge might start to cycle, but for the moment I've just been keeping up on the WCs and using a turkey baster to remove waste when I see it. I've been testing daily and haven't had any spikes to speak of yet since the bowl was set up. There was an initial small ammonia/nitrite spike a few hours after tank setup, but that hasn't repeated itself so I presume it was due to dieoff of what was in the small amount of actual sea water that got mixed in (since you can't exactly poor a jelly safely into a net to move it).
Right now I'm just feeding it live brine. I'm going to switch it to probably half live and half refridgerated plankton mix today though using a pipet to target feed and minimize waste. It goes through a frightening amount of live food that will have me making a lot of LFS trips if I don't switch it over, since I'm not set up to produce brine shrimp on the scale it wants currently with 2-3 feedings per day. At first it would periodically try to eat the glass and airline tubing, but it seems to have learned not to do that, which is pretty amazing given the absence of anything brain-like in these animals. The issue of getting caught on relatively smooth things like airline tubing seems to be a myth, at least with this species. I would imagine this is why the Norwalk Aquarium I posted pics of previously to is able to us mesh partitions successfully without having jellies plastered all over the mesh. Attempts to eat the airline tubing had me wondering if it had actually tangled itself (it was a knot of tentacles), but in literally a few seconds it can just let go of things, untangle, and swim away as though nothing happened.
I don't anticipate a huge, long-term success with this jelly, since among other things, this is a single adult that may be full grown and I don't know where it is in its life cycle. How long they stay in the medeussa stage is also up in the air; I've read anywhere from 2 months to 2 years for this species. Whether that's a lifespan in terms of time until killed by the environment/predators or time until some other natural death I don't know. So, this tank could last days or months, but regardless of how long I'm able to maintain this setup, it has already proven very educational and to me is therefore worth sharing.
If I do another one of these sorts of things in the future, from what I have seen so far I would probably go for a large plastic tub to be able to keep more than just a single jelly. One thing I don't like about the bowl is that there is no way to safely reach in there with a hand. Going in bare-handed would obviously be insane, and probably the jelly would try to eat gloves, which would risk me hurting it. More space would mean easier to reach in without snaging a jelly, and operating purely with tongs and turkey basters can be a bit tricky with a narrow opening at the top. A larger/wider setup would also allow for mesh partitions to have more equipment (perhaps some LR to decrease the need for WCs).
