chemicals in the native tank to kill hydra

[Sophia]

Unfortunately my bugs tank has got hydra already :evil: ... many bugs are now out of sight, only the water boatmen, snails, a couple of shrimps and some fast moving pods are still visible. There are no fish or other critters that I know of, so if I have to I will treat what's left and then get new bugs if they all die.

I've had a hunt about the archives and found a range of solutions but does anyone know which of these are suitable for this scenario, and what the dosage would be for a 22 litre tank? I have panacur/fenbendazole, salt, formalin, snail rid/copper.

Tank has no ammonia or nitrite and very low nitrate. Ph is 6.4 to 6.6 and I have not tested the kH but I doubt it is anywhere near the 5 drops of test kit you need to be able to use snail rid safely in a fish tank.

I am prepared for all round deaths, though not ideal so if there is a less painful solution I would like to try that first.

On another note, hydra itself is quite interesting. If it weren't a killer bug, I would keep it for it's anemone-ness :-?

[blueether]

looks like salt or Hydrogen Peroxide might work

http://www.aquariacentral.com/forums/showthread.php?t=82066

[alanmin4304]

Formalin at 12 mls/100litres will do it but is toxic to fish and plants at that dosage.

[Sophia]

The next question is, if I go back the creek for more shrimp or bugs, when I drag the net on the weed to catch shrimps, is that enough to pick up more hydra or would it have been physically attached to the plants I got? It certainly wasn't visible when I put it all in the tank, it appeared afterwards.

[alanmin4304]

There is always a risk of picking up creebies like that with live food unless you start with a clean culture and grow them yourself.

[Sophia]

can you buy daphnia 'seeds'?

that was my original idea for the tank and then I got off track :oops:

[Stella]

Are you sure it is the hydra?

My critter tank has had hydra for ages, but in very low numbers. (A freshwater anenome, how cool is that!)

Though my tank is now a wasteland - very little alive, even the snails have vanshed! I am blaming the damselfly larvae I put in recently, despite not having seen any since. It is all very weird. Even the tubifex are gone.

[Sophia]

there are some in the moss that look like this http://scienceblogs.com/gregladen/hydra-opsin.jpg

and some that haven't got the multiple prongs on the top yet. Also ones that move without the prongs attached to the glass.

What else could it be? I found the remains of a shrimp casing yesterday and there are few or no daphnia left, certainly no running about the floor like when I first set it up. Maybe they all died a natural death but it's extremely coincidental that these things turned up and everything else went quiet. The only thing is that some of the leaves have made a bit of wispy mould as they rot down, some I have removed, otherwise I thought that was natural and OK.

:dunno:

[blueether]

I wouldn't have thought their population would explode :dunno:

My daphnia population has crashed in the last few days, much less light with all the rain and two large diving beetles turned up in the main tank about 3 or 4 nights ago, cool that they just arrived :happy2:. They got moved to the bug tank as I didn't want the inanga to eat them like they have with all my shrimp.

Oh and shrimps do grow out of their 'skins'

[alanmin4304]

not planaria?

[Stella]

Daphnia can die off if they don't have enough food (suspended bacteria/algae) but the leaf litter decomposition should be starting a bloom off.

Hydra are very very very tiny, very hard to see, and the tenticles are even tinier. And they are violently green. The moving ones could be planaria (~5-10mm long at most):

http://islandwood.org/kids/stream_healt ... arian2.jpg

(COOL hydra pic, I had to search down the blog it came from, will read it later)

Well done blueether on having the diving beetles arrive! I adore diving beetles (were the point of my first critter tank). They are quite mobile and can fly (as you have noticed!) so a lid will stop them from escaping. They like a bit of ox heart or other meaty goodness. They are quite hungry little guys, but seem to be mostly scavengers as their eyesight seems really bad.

Do a search on diving beetle larvae.

[blueether]

"Do a search on diving beetle larvae"

I have caught a few of them out at mums pond (and some adult diving beetles yesterday*) they have become fish food

Oh I just spotted one of my dobsonfly larvae in the main tank, man it is getting big - bigger than most of the bullies

* they were both covered with our native leeches a quick salt bath sorted the leeches out and the 2 beetles seem to be recovering well and not as lethargic as yesterday

Sorry Sophia for the off topic-ness

[Stella]

Dobsonfly larvae are awesome I took two home once for my kokopu to eat. The kokopu had been in captivity since they were whitebait so had never had a chance to try dobsonfly larvae before. They sucked them in, spat them out immediately and had nothing further to do with them! It looked like maybe they tasted bad.

Beetles covered in native leeches... weird. Sure they were actual leeches and not planaria? Either way I doubt that they could harm the beetles. Their exoskeleton is AMAZINGLY hard (as in 'is this a beeltle or a stone?' hard!) and covered in waxes that make them very slippery and reduces drag in the water.

(I pinned one of my huge 1" diving beetles once, was very hard to hold onto, and I had to heat the pin to burn it through the exoskeleton, and still thought the pin would self-destruct before the beetle did. I have seen a photo of big diving beetles for sale elsewhere as food - teeth-breakers!

(do another search, overseas diving beetles (Dytiscidae) are popular pets)

[blueether]

Must be something in the air today there are 3 dobsonfly larvae out :-?

leeches, looked like this one:

http://www.waitakere.govt.nz/AbtCit/ei/EcoWtr/macroinv/images/Leech2.jpg

If they were not feeding they were defiantly slowing the poor things down, two on one and 3 on the other.

Edit, got another one:

Any way back to Sophie’s problem, you have pics on the critters Sophie?

[Sophia]

will post some later when I'm at home again

[Sophia]

Update after I got a light over the top and poked about.

3 shrimps remaining alive, the rest dead. Even tiny dead shrimps stink like hell :sick:

Took the leaves out of the water as there was an oil slick on the top which reminded me of the same one I had when I had the rotting wood in the killie tank. Maybe the wrong sort of leaves, maybe too oily. Have now got 3 oak leaves and a beech or something, much more papery thin.

1 dead big water boatman. Snails still OK and so are the white leechy things on the tank glass. Some look and move like slugs, the rest stay still.

Siphoned out about 6 litres and replaced with clean dechlorinated water. There are a few pods alive, definitely no daphnia anymore.

See what you think of these photos: click the thumbs for better look. Top 2 are movies of a few seconds

worm/anemone and remaining green ostracod

Another worm/anemone bottom right, then you can just see the hydra after the camera moves

Bugs on the glass – approx 2-3 mm long, bigger and thicker than the planaria I have seen in the killie tank

Nice still shot of anemone worm – if you approach it it retracts quickly like a sea anemone

Hydra – there were about 3 of these, currently in hiding after me fiddling about

The Horror

[Sophia]

the anemone worm things are waving about of their own accord - there is no current pushing them.

This morning the oil slick is gone, the hydra (?) is back in the moss and the other worm/anemones have reappeared. No new shrimp casualties apparently

[Stella]

Hmmm, I am reminded of something a while back, someone here found that dechlorinator chemicals are toxic to crayfish. Crays are curstacea, like copepods, daphnia and shrimp. maybe this was the problem?

Did the tank have a cover? Often oil slicks are stuff that has settled from the air onto the water surface. My tanks get dreadful slicks in summer when I am using fans for evaporative cooling - increases the amount of air hitting the surface.

I haven't seen slicks from leaves, but I really don't know much about what leaves are safe (probably most).

For some reason I can't open your pictures at work (problem at my end not yours), but I think your worm is probably a tubifex worm (or similar). They come out and 'wave' in the water when there is little oxygen. My tank can become a meadow of waving tubifex at times. Put in a bubbler and they are all tucked back into the sediment within 24 hours.

I am going to try and repopulate my critter tank today. Really not sure why everything has dissappeared in mine too, all a bit odd. I figure oxygen or water chemistry, but the fish is still pootling around, and some damselfly larvae have hatched. There are so many hiding places I am less inclined to think it could be predation now.

[Sophia]

Are tubifex worms harmful to the other critters do you think?

Re the dechlorinator chemicals, the first tank fill was solely rainwater off from the roof that I caught from the downpipe. Yesterday's water change was a third dechlorinated water and there are still pods swimming about. Also I still have the original shrimp that was to become killie dinner still living apparently happily in there where it's only dechlorinated tap water. Maybe it's only some chemicals, or maybe I have found a hardy shrimp!!

I don't have a cover on but I do think the oil slick is from the decaying matter - those leaves I had in there were mostly fruit trees and were thick plasticy leaves, full of life giving sap no doubt. Also there were a few pohutukawa which was the same wood that I had in one of my older threads and there was a big oil slick while that was rotting away too. I don't know if anyone else has noticed this.

Today is also More-Pod day for me, am going back to the trough to get more bugs and see how these guys do. Yesterday my husband tried to take me for a walk around the park and I spent half the time running about looking in sheep troughs instead of being attentive :roll:

[Stella]

Are tubifex worms harmful to the other critters do you think?

I think they just eat decaying matter.

The critter tank is like a mini-ecosystem. With mine what I want to create is a whole lot of self-sustaining populations of whatever survives or appears. I chuck in a whole lot of bugs and some will keep on going. The leaf litter and peat decomposition forms the basis of the ecosystem, along with the sunlight creating algae. Snails and daphnia eat them, they get eaten by other things, who get eaten by other things. The diving beetles are the top predator, and these (plus the damselfly larvae) are the only things that can't form self-sustaining populations in there due to lifecycle issues.

those leaves I had in there were mostly fruit trees and were thick plasticy leaves, full of life giving sap no doubt. Also there were a few pohutukawa which was the same wood that I had in one of my older threads and there was a big oil slick while that was rotting away too.

AH, there might be your problem! Next time gather dead brown leaves that naturally fell off the tree. Also don't use 'fresh' wood or sticks.

Yesterday my husband tried to take me for a walk around the park and I spent half the time running about looking in sheep troughs instead of being attentive :roll:

hehehehe that was your final test, you are now one with of critter people 8)

[Sophia]

haha

I've just updated the other thread - what my tank lacks is a definite purpose at the moment. If I hadn't brought the shrimps home I would have made things easier for myself. At this stage I'm not adding chemicals but I will see if the addition of more bugs is a success or if they disappear as well. If they die I will start again, or turn the tank into something else I have more knowledge in. Who would have thought making a puddle would be so complicated.

(I did gather fallen leaves - anyway they are all gone so never mind. And the oil slick isn't gone, I just didn't see it haha. The mystery of the slick remains )

and now off to the park