Hydra found in tank

[Bradleyh91]

Hello,

I don't know if this is in right section but didn't know where else to put it. I have just been informed that by the looks of it I have hydra in my planted tank. It's fairly heavily planted only had two Otto's in at the minute but was just about to put my dwarf puffers in however holding off for a minute. Does anyone know how I can remove them without damaging my plants?

Many thanks

 

[BigTom]

Flubendazole is extremely effective against hydra - Hydra removal | UK Aquatic Plant Society

 

[three-fingers]

Why? Hydra are basically harmless and very interesting critters. Unless your breeding very expensive shrimp (and I somehow doubt that if your putting puffers in there!), any actions to remove hydra would be a total waste of time and resources IMO.

In my shrimp tanks I just ignore them as I think it's very rare for them to catch even newborn shrimp. I believe they mainly feed on copepods, although some hydra enjoy symbiosis with algae allowing them to photosynthesise just like sea anenomes (which are in the same phylum as Hydra spp., both being cnidarians).

If you used chemicals to get rid of them, they would probably re-introduced soon enough anyway, even if you don't notice for months.

 

[Bradleyh91]

I read online that they can potentially kill small adult fish and also can eat fish eggs? This is the only reason I was worried about the puffers, and you're right I won't be putting any shrimp in the tank.

 

[dw1305]

Hi all,

In my shrimp tanks I just ignore them as I think it's very rare for them to catch even newborn shrimp. I believe they mainly feed on copepods, although some hydra enjoy symbiosis with algae allowing them to photosynthesise just like sea anenomes (which are in the same phylum as Hydra spp., both being cnidarians).

They are really cute, but they are very efficient hunters of nearly all small crustaceans, and can spread alarmingly if you feed micro-worms, Daphnia or BBS. They will definitely catch and eat small shrimplets.

The green Hydra viridissima is the one I normally have, it isn't as actively predatory as the non-symbiotic ones (it usually just sits in the light photosynthesising), but it spreads more quickly and anything that bumps into its nematocysts is toast.

cheers Darrel

 

[darren636]

[quote="dw1305

The green Hydra viridissima is the one I normally have, it isn't as actively predatory as the non-symbiotic ones (it usually just sits in the light photosynthesising), but it spreads more quickly and anything that bumps into its nematocysts is toast.

cheers Darrel[/quote]
even the incredible hulk?

 

[three-fingers]

I read online that they can potentially kill small adult fish and also can eat fish eggs? This is the only reason I was worried about the puffers, and you're right I won't be putting any shrimp in the tank.

Some adult micro-fish like microrasboras are maybe at risk from stinging injury but not capture, but nothing you would keep with puffers anyway! Personally I've yet to see a hydra manage to capture a shrimp, I've seen baby shrimp dart away easily enough after being stung though. I may just have tough shrimp or wimpy hydra however! Since hydra are essentially sessile they would only eat fish eggs that are laid directly on them, so they are less risk than your filter inlet . You may even find the puffers eat the hydra! (I've seen my paradise fish and others munch on them)

As long as your not feeding the tiny live foods that Darrel mentions frequently, they shouldn't get too numerous that they are an annoyance for the puffers . I've actually tried to establish green hydra in my shrimp tank lol just to have a change from the normal ones. An interesting fact about Hydra spp. is that they are thought to be biologically immortal, this means they cannot die from old age. They also have regenerative powers, give them adamantium tentacles and they would be a worry in the tank lol!

 

[Bradleyh91]

So basically I can leave them in there and the puffers will be fine? I just don't find them very aesthetically pleasing but main concern is for my other tank inhabitants lol

 

[three-fingers]

Yup, basically. I would consider a few hydra "enrichment" for the fish, something natural to interact with like they would in nature. Possibly even eat. It's only if you have thousands of them lining all the surfaces of the tank that they would bother the fish at all. Then you could use toxic chemicals if you liked, but they would come back unless you changed the tank so that they had no food (nearly impossible).

You'll most likely stop noticing them a while after the puffers are introduced .

 

[Bradleyh91]

Ok thanks for all your advice!!