Monday, November 7, 2011

A Jellyfish Emergency; When Hydrozoans Attack!

Hydrozoans are like the bad cousins of jellyfish. They can deplete your tanks nutrients, cover your tank walls and most importantly, damage or kill your jellyfish.

Earlier this year in march I witnessed a major hydroid attack on my jellyfish. I had no clue what was going on, as I was not expirenced. All I could understand was that something was making my jellyfish very sick. I did nothing to stop the undetected attack and my jellyfish died. My three jellyfish began acting very strangely. They slowed down and began to become very soft and gooey. Obviously moon jellyfish are already gooey, however it seemed like my jellyfish were beginning to melt! The jellyfish spent their time stuck to things such as the substrate or sadly, even the heater. Eventually the jellyfish withered away like a block of melting ice, leaving me with several questions. The tank was empty except for a snail and two hermit crabs. I began to notice this intricate spider web design on the acrylic near the bottom of the tank. I was searching for polyps, and at first I thought I found them, however I later realized that I ran into hydroids.

Hydroids are simply the polyps of hydrozoan jellyfish. They live in a network style colony, forming branches with little buds at the end of the branches.

I watched these strange hydroids for a while, and to my surprise they began to produce small jellyfish. These new jellyfish were very strange. They were very simple and didn't do much. In fact they pretty much latched onto the walls of my tank and stayed their until something disturbed them. They didn't get very big either. At times I would have 20 or 30 of these things. And then their populations began to decrease. They were draining my tanks food and I didn't feel like replenishing it. Then of course I ended up knocking my tank over, and wiped out their population.

video
A video of some hydroid jellyfish found in my tank in march. 

Im sure your thinking this is a nice story and all, but why? Well I realized yesterday that their are hydroids present in my tank again. I think they hitched a ride on my clown fish and were accidentally introduced. My first thoughts were to nuke the tank with bleach. But then I began to question that. nothing in my tank is any different. My jellyfish are healthy, as are my clownfish and snails. These hydroids may produce jellyfish, and possibly a new jellyfish Im unfamiliar with. So I decided I would attempt to remove them and grow them elsewhere. Well I scraped as many as I could see off, and put them in a flask. They grew back almost immediately in the tank. The colony still seems small though, and there is no sign of any hydroids gearing up to produce jellyfish. They just seem to be busy eating. in fact not all hydroids produce jellyfish. These may just stay hydroids. However I hope that they produce something cool while they loiter in my tank.

So I'm just going to watch the colony and intervene if something goes down. My next segment of this will be on the removal of hydroids and what you can do about them.

Picture credit~
http://kentsimmons.uwinnipeg.ca/16cm05/16labman05/lb5pg4_files/image002.jpg

22 comments:

  1. I have three jellyfish, and searching on the web i found this website, and seems that you have the answer to my problem. I have 3 moon (warm watter) in my tank, one of them does not want to eat, so its been shrinking, and now stuck to the wall as you said, I have seem some of those spider web type of thing in the heater.....what do you recommend me to do? (charas6@hotmail.com)

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  2. just to let you spider web type of things are gone, looks like snails ate them all.

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  3. @Anonymous

    Are your jellyfish any healthier? Let me know if the web like structures return.

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  4. no, there are no web like structures, tank is very clean, 3 snails have been close to the heater for a couple of days, i dont know if they were algae or something else but seems like they ate them, and very clean now. bad news is that sick helly is still stuck to the acryllic wall and even smaller.

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  5. I dont know what to do!

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  6. @Carlos

    Does he appear to be almost melting or falling apart? and is he near the heater?

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  7. Last night it had the oral arms hanging down, but i fed them this morning and it even swam around the tank for a while (didnt happen when i fed them last night) i usually feed them once a day, and i started twice today, its been stuck to the wall not near the heater at all, its totally in the opposite side, eventhough this morning it started moving closer to the heater, but still about 1/4 for the tank apart. I think it doesnt look like melting, i have a picture, just dont know how to upload it here.

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  8. @Carlos

    You can send me the picture at {Travis.brandwood@gmail.com}. I sounds like your jellyfish might just be going through a stage. sometimes jellyfish will form a round suction cup shape and stick to the side of the tank.

    If your jellyfish is shrinking it may not be getting enough food or perhaps not the right food. Try feeding it frozen brine shrimp, squid, mysid shrimp or other frozen foods from petco. Or if you can, feed it live baby brine shrimp.

    Send me the picture, and I will take a look at it.

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  9. i just sent you the e-mail, you should getting it shortly, how do you feed them with frozen shripm, and that stuff? i have only given them the frozen food (plankton with nutrients) that they sell at jellyfishart using a pipete.

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  10. @carlos

    I got the email, but the pictures were distorted and were comprehendible.

    The frozen shrimp is the same. just dissolve it in a dish and feed it to the jellies with a pipet like you would with the jellyfish art food. Hope that helps!

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  11. Just resent the email from a different account, i think previous went wrong due to email format. let me know if you get it and what you think, you will see which one im talking about, i sent you a video as well.

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  12. @carlos

    Your jellyfish seems to be okay. :) It should stop doing that after a while. My jellyfish did the same thing when i first got it. check and make sure the water temperature is alright and then try doing a water change.

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  13. i fed them twice today, and did a water change....
    hope it will get better, i see a strange behavior in the big ones as well, everytime they swim closer to the bottom and stick to the wall as well, hope they wont shrink or happen same thing....today when i got back from work one snail was dead, out of its shell, i thing theres something else wrong

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  14. @Carlos

    Just watch your jellyfish carefully. Jellyfish do act strangely sometimes. If your jellyfish get worse just contact me.

    Im not sure what happened to your snail. It could have been old or it could have been attacked. I'm not entirely sure.

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  15. I just sent you another email, small jelly is getting even smaller and opaque or blurry, and the big one is not sticking to the acryllic wall, it seems to have a blurry spot in one of the edges....

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  16. i meant the big one is now sticking to the acryllic wall

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  17. @carlos

    How long have you had your jellyfish? Mine did the same thing when I first got them. They were fine after a few days. The reason they did that was because they got stuck in a snow storm on the way to my house in the mail. So they wee very cold when they got to me. they perked up later and started doing this for a day or two.

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  18. i`ve had them for 2.5 weeks now...temperature has been at 77

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  19. @carlos

    Alright. How high is the water in the aquarium? Is it about an inch above the bubble tube? Your jellyfish are new, and they may be still getting used to the aquarium. If the water is too low or too high in the aquarium, then they jellyfish may not be getting enough flow.

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  20. it is 1 1/4 in, (little bit more than one inch)above the bubble tube

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  21. @carlos

    Okay thats fine. Perhaps your jellyfish are just getting used to the tank. Make sure they are getting food, but also make sure they aren't getting too much food, that could make the water too dirty.

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  22. my jellyfish are doing the SAME THING i got them from Jellyfish art 2 weeks ago and everything seemed fine i got 4 of them and i found the bigest one stuck to the side of the tank when i got home from work and saw that it was basically melting and he shrunk ALOT i tryed to feed my jellyfish after this and one one of them were really eating and i did everything the Jelly fish art website said to do PLEASE HELP how do i get them better and i have one snail in my tank maybe did the snail bring along some disease or Hydrozoans EMAIL ME AT forgetbrandonbogush@yahoo.com or call me at 1-860-462-6590

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