Hydra - big problem or little problem?

[RovingGinger]

I am not sure if hydra qualifies as general discussion or a disease? I found a small population of water hydra in my guppy fry tank. For a while I was taking them out on the rock they were attached to and seeing if the pea puffer was interested (no). From observing, I never saw a fry get caught or close to caught by one. The fry eat floating detritus worms and they sniff at any floating hydra but then go ew and swim away. 

I know they’re a sign of over feeding, but I’m worried about balancing that against accidentally starving fry. Are they something to be legit worried about or do I just run some mollies through the tank once the fry are out or what? 
 

 

[Wmarian]

They are indestructable immortal beings. I kid you not, they reproduce by cloning so all identical back several million years and if you smoosh them each piece likely to be new one. They spread readily in the tank, can arbitrarily decide to let go and try another spot, and annoy the heck out of me. I also have a massive infestation of them in my fry tank and haven't noticed any losses or injury. I hear flubendozol (sp.?) works, but not sure of impact on other creatures, inverts and plants. Here is a link to a cool you tube channel that talks about their history like they are the best little critters ever. My vote is no worries, maybe try to get rid of them when fry gone.

 

Edited July 16, 2020 by Wmarian
Edit

[Daniel]

5 hours ago, Wmarian said:

They are indestructable immortal beings. I kid you not, they reproduce by cloning so all identical back several million years and if you smoosh them each piece likely to be new one. They spread readily in the tank, can arbitrarily decide to let go and try another spot, and annoy the heck out of me. I also have a massive infestation of them in my fry tank and haven't noticed any losses or injury. I hear flubendozol (sp.?) works, but not sure of impact on other creatures, inverts and plants. Here is a link to a cool you tube channel that talks about their history like they are the best little critters ever. My vote is no worries, maybe try to get rid of them when fry gone.

 

My vote also is no worries. I would mostly prefer not to have them. I have never seen them eat fry. The biggest problem for me is that they eat more than their fair share of the baby brine shrimp or daphnia that I put in the tank as fry food. The hydra get little orange bellies just like the fry! If I weren't biased against them I would see them as micro sea anemones and think they were the coolest thing ever. 

[Alexa]

I had an issue with them in my shrimp tanks. Lucky for me, spixis aren’t illegal in my state, so I added one to each tank and the hydra were all gone eventually. It was an expensive solution but I got cool snails out of the deal.

That being said, I’m on the “no big deal” train unless they actually start hurting your livestock.

[MickS77]

On 7/15/2020 at 11:10 PM, Wmarian said:

They are indestructable immortal beings. I kid you not, they reproduce by cloning so all identical back several million years and if you smoosh them each piece likely to be new one. They spread readily in the tank, can arbitrarily decide to let go and try another spot, and annoy the heck out of me. I also have a massive infestation of them in my fry tank and haven't noticed any losses or injury. I hear flubendozol (sp.?) works, but not sure of impact on other creatures, inverts and plants. Here is a link to a cool you tube channel that talks about their history like they are the best little critters ever. My vote is no worries, maybe try to get rid of them when fry gone.

Just to add to this thread. I recently had hydra, for the first time, hitchhike into my 75 gallon tank. The tank just has a lot of leaf litter and branches in it right now. I added some crypts and java fern, also noticed a few snails came in too. I'm still letting the tank establish so no fish yet. After a few weeks what I thought was just normal algae turned out to be green hydra. I treated the tank with a single one gram packet of canine dog dewormer containing fenbendazole. I mixed the powder in a jar with water then poured it in the tank. That killed the hydra almost immediately, i could see them shriveling up. It has been over a week, the plants and snails made it through fine. No sign of hydra resurgence. I don't know fish would do. I'll probably do a few more water changes and add some carbon to filter before adding fish to the tank.

[Daniel]

Just now, MickS77 said:

...canine dog dewormer containing fenbendazole..

Wow, that's good to know! What gave you the idea to try that?

[MickS77]

2 minutes ago, Daniel said:

Wow, that's good to know! What gave you the idea to try that?

Just a google search for getting rid of hydra haha, thought I'd give it a try. 

[Diego]

The bad side of fenbendazole is that your tank will be inhospitable to snails for several months no matter how much active carbon you use. The canine version is also poorly soluble so it stays in the substrate for long (slow release). If you can change the substrate it would help.

There is a goat dewormer which is liquid and works better than the dog one. I used planaria zero and it worked against hydra too but has the same effect on snails.

[Diego]

Just to make clear, dewormers are very hard on your aquarium. They will kill hydra, planaria and any other worms (good ones too) and snails. I will use them only as last resort.  

Dewormers will not kill leeches ... just in case you were asking that 🙂

[H.K.Luterman]

I think they're kind of neat. There's some in my bichir tank and I thought they were so interesting I took video of them. X3

But in the tanks where I have fish fry, I put in single mollies for hydra duty, just out of nervous precaution. 

[RovingGinger]

Hydra eating a worm in one of my guppy fry aquariums. A fry comes to check out the wiggliness but quickly leaves, this fits with what I have seen in terms of fry just avoiding being too close to hydra in general. Maybe with smaller fry born from eggs it would be more of an issue.

Edited August 3, 2020 by RovingGinger
Fixed embed

[MickS77]

Very interesting, surprisingly strong grip! 

[Daniel]

Turns off they were very afraid of hydra in 1934!

Oh no, Mr. Bill!

Nevertheless I am still not worried.

 

[Jill c]

On 7/16/2020 at 4:10 AM, Wmarian said:

They are indestructable immortal beings. I kid you not, they reproduce by cloning so all identical back several million years and if you smoosh them each piece likely to be new one. They spread readily in the tank, can arbitrarily decide to let go and try another spot, and annoy the heck out of me. I also have a massive infestation of them in my fry tank and haven't noticed any losses or injury. I hear flubendozol (sp.?) works, but not sure of impact on other creatures, inverts and plants. Here is a link to a cool you tube channel that talks about their history like they are the best little critters ever. My vote is no worries, maybe try to get rid of them when fry gone.

 

I had trouble with hydra in a few of my nano tanks I didnt want to use any chemicals with having shrimp so I got some spixi snails they got rid of it all I have them in all my tanks now as they bred i gave my mum some as she had hydra and hers as now all gone their a nice addition and only breed if you have a male and female together 

[MR aquarium]

i anyone really just wants them gone and they wanna do it cheap i hear salt works really well with hydra for the reason that they have a very weak skin made mostly of water so they dehydrate fast. this is just my opinion and they will probably not harm fish at all if salt fails then you can go ahead and try what micks77 said.