Hydra, How to get rid of it

[Grace]

Ive had a cherry shrimp tank going on for a short while now when i noticed some ostracods sharing the tank. Ive also noticed some hydra after the ostracod population went crazy!! I have no idea how the hydra got there since i havent added any new shrimp or plants. So how cani get rid of these hydra with out tearing down the whole tank.

[PhishPhreek]

Re: Hydra, whats the best way to get rid of it?

To eradicate hydra there are many methods. I have tried two.
One method is to add 5 grains/gallon (78 ppm) of ammonium nitrate.
Another is to heat the tank to 106 F for ten minutes removing the
fish of course. Both methods are safe for both plants and fish.
--
Dave Whittaker
ac554-at-FreeNet.Carleton.ca

Aquarisol works well against hydra and is fairly easy on the fish and
plants. It is a copper based medicine, but I've used it without ill
effects in tanks with rainbow fry and planted aquaria. You may want to
try a half dose at first, to insure your julies aren't sensitive.
Those hydra can really reproduce when you're feeding baby brine, can't
they? I would also warn you to isolate anything you use in that tank.
You can easily move hydra around with nets and such. Then they'll show
up in a fry tank as soon as you start pumping in the baby brine.

http://pw2.netcom.com/~caryho/home.html

It's really quite interesting to watch this battery and wire setup at work,
I didn't have a six-volt battery lying around, so took a set of  eight AAs, soldered them in parallel by pairs and then each pair in series  to not only get the six volts but with a higher loading capability than simply stringing four in series. As soon as they're in the water, the cathode begins to trail a stream of really fine bubbles, and after a while the anode begins to get the green build-up charateristic of weathered copper. At any rate, the hydra began dropping within 20 - 30 minutes. The tougher ones held out for about two hours.   It's recommended to keep the electrodes in the water for three to six hours, followed by an immediate 25 - 50% water change for those interested.
nestor10-at-mindspring.chkr.com

[Mzungu]

Re: Hydra, whats the best way to get rid of it?

Just be careful if you use any medications. They'll most likely contain copper, which would be fatal to your shrimp, and tends to stick around in the aquarium for quite a while.

Try doing more water changes, as well. Might diminish the hydra population.

[Grace]

Re: Hydra, whats the best way to get rid of it?

I'll be doing the heat up the water to 100+ degrees. I dont want to risk any traces of copper in the tank.

[Brownsnoutuk]

Re: Hydra, whats the best way to get rid of it?

I never heard of Hydra before - heres a cool link if you wanted to learn more.

http://en.wikipedia.org/wiki/Hydra_%28genus%29

[turtle]

Re: Hydra, whats the best way to get rid of it?

agree on the "beware of copper"....  I don't know of any inverts that tolerate Cu very well....

[Spot86t]

Re: Hydra, whats the best way to get rid of it?

Wow, I'm having the exact same problem.  What was once a loaded cherry tank now has been reduced to a mere 2 dozen or so.  I read up on the hydra and it's likely they've been eating my cherry fry.  I had a bristlenose in there as well.   From what I read, it gets anywhere - plants, substrate and I saw some on my sponge filter.  

This morning I relocated the (desired) residents to a bare 10 gallon with a sponge filter robbed from another tank (whose inhabitants I had to disperse so I could use their filter).  I also noticed some of my other tanks have them too.  The affected tanks are all 10 gal, and contain 1 procambarus alleni crayfish, 8 or so guppies, and 3-4 amano shrimp, and a few have snails.  About 6 tanks have this infestation.  

I watched last night as a snail was crawling (oozing? What DO you call a snails method of travel?) along the glass and came to some hydra.  I can only presume that's when the hydra stung it, as it retracted a little, then just seemed to gobble it up.  That particular tank has a LOT of snails, but I guess they don't all find them tasty or something cause theres LOTS of hydra in there too.  I plan on picking up some potassium permanganate to treat some wild lake plants before introducing them into my tanks, and will dose one of the affected tank with some to see if it eradicates them (out of curiosity).  If I find I don't have time for all that experimentation I'll just bleach the tanks, scrub and let dry.  I hope the potassium stuff works tho cause I saw lots of hydra in the anachris and java moss that was in the tanks.  Copper is definitely not an option - because of the crayfish.

If anyone knows if Potassium Permanganate kills it, please let me know!

Spot

[Mzungu]

Re: Hydra, whats the best way to get rid of it?

I wouldn't dose the tank until you know exactly what you're doing. Potassium Permanganate is powerful stuff. Like I said in the other thread, I think Szidlon doses her tanks, but in tiny, tiny amounts. As long as there is nothing living (desireable) in the tank, you could rinse it out with a PP mixture, but as it kills snails as well, I wouldn't risk your shrimp. After that, use a lot of dechlorinator in some rinsing water, as that's supposed to neutralize (can't think of the other word) PP. Then make up some normal tank water.  :)

I've had hydra in the past, but never enough to call it an infestation or outbreak or anything.

[PhishPhreek]

Re: Hydra, whats the best way to get rid of it?

I've seen a few notes where livebearers and gouramis eat hydra

[JLawson]

Re: Hydra, whats the best way to get rid of it?

Did y'all notice in Brownsnoutuk's link that Hydra are "biologically immortal" - and a new word for me - "senescence" which is derived from the Latin word senex meaning 'old man'.  Anyway, I'm still curious about how these found their way to your tank.

You haven't added anything new, the ostracods appeared first... so the origin of the ostracods is also a mystery.  Maybe they were both introduced with a food source?  Transferred from another tank by a net or cleaning tool or shared bucket?  Both Grace and Spot86t report the problem in a CS setup... did you get your CS from the same place?

I think this is interesting epidemiologically because to detemine the source and to understand the nature of the Hydra's proliferation might enable us to prevent this in the future.  Or maybe I just like a mystery.  :)

[PhishPhreek]

Re: Hydra, whats the best way to get rid of it?

Well, I've been flooding my frytank with BBS and now I have HYDRA everwhere

Found this on the net - one quarter of a grain of potassium permanganate can be added for each gallon of water. The dosage can be doubled if there is no fry. This should be left for two or three days and the water then gradually changed until half to two thirds of the original has been replaced. The fish need not be removed.

http://zda-fishenthusiast.blogspot.com/2007/06/how-to-eliminate-hydra.html

Anybody know how to measure a grain ?

So special thanks to NKS for selling the potassium Permanganate at the HAS auction.

[szidlon]

Re: Hydra, whats the best way to get rid of it?

I'm not so sure on using PP with fry in the tank.  I can tell you how I use it on my larger tanks.  I take 1/4 teaspoon of PP and disolve it in a pint bottled water container.   I pour the mixure into the tank until it turns a med to dark purple. I keep a bottle of hydrogen peroxide right next to tank to neutralize the PP if the fish are showing any signs of stress, about a capful of hp will work.  Once the water turns brown the PP has done all it can and you can do a water change.  Since PP is not descriminate of what bacteria it kills I turn off my filters until it's done but keep a good amount of circulation with an airstone or powerhead.

PP can be really stressful on fish, especially if it's overdone which is why I don't think I would use it in a tank with fry.  Can't you just cut down on the feeding and the hydra will just die off?

[PhishPhreek]

Re: Hydra, whats the best way to get rid of it?

1 grain = 0.06479891 grams
1 gram = 0.03527396210511196 ounce
.25 grain / gal = 1 ounce / 1750 gal
2 - 4oz baggies should treat 14,000 gallons.

My main concern is the hydra eating my fry or the pp killing my fry.
My secondary concern is pp killing my java moss.
It has already spread to 4 of my fry tanks.

Nothing beats live wiggly food.
guess I can go back to my powdered dry mix..................
I use decapsulated brine shrimp eggs, golden pearls & ground shrimp powder & Just got some freeze dried rotifers & spirulina Powder from brine shrimp direct
should make a passable mix.  



I just don't see any way to measure a safe dose.

[szidlon]

Re: Hydra, whats the best way to get rid of it?

In all honesty, I don't think any dosage would be safe for fry, they stand a better chance against the hydra.  What kind of fry, or can I just guess Betta?

[PhishPhreek]

Re: Hydra, whats the best way to get rid of it?

Yes,  my November Betta Spawns