Whats Eating My Tetras & Nipping Corys :(

[DizzyMoo]

Hi everyone, Hope someone can help me here. Something has been eating my tetras at night time, I thought it was the male of my 2 paradise fish as i saw him constantly chasing everything so i rehomed them seen as they're a pair, But nope it still kept happening i was waking to 3, 4 sometimes 5 tetras gone in a night no sight of a tail or half a body nothing, So i searched online what else could it be... i got some links saying the featherfin catfish i had will eat tetras & links from others saying that their featherfins had been eating the tetras so before i found him a home i left the tank light on at night instead of turning it off & hey my fish were fine...but then 1 morning i noticed 3 tetras missing, convinced it was the catfish i rehomed him ... THEN the night he is rehomed 3 more tetras bloody disappear!
In total i've had 15 tetras suddenly go awol within 2wks, I really don't know what is going on. Its been going on longer but as i added 15 tetras the last 2wks i kinda noticed them disappear more so, Checking out whats left of my fish this morning i noticed 4 corys have what look like nipped fins & 2 of the remaining 5 tetras have their tails missing
Oh & 1 of my guppies suddenly disappeared during 1 of these nights too, I kinda started thinking that maybe there was a disease problem or water problem & that somehow they committed suicide at night & the pleccy was having a midnight feast but i'm now on the verge of completely giving up & selling everything.

I have a 4ft tank, sand substrate, bogwood & live plants ...

Fish that are now left are :
5 *mickey mouse* platys
2 *batman* platys
3 guppies
5 peppered corys
1 plec (3inch)
5 tetras


So ok come on guys who's eating them, Is it the platys? None seem fat or like they've had a midnight feast, Watching them they all seem fine & healthy swimming round together & on their own i haven't seen any fin nipping,chasing or anything whilst im in the room watching. Water conditions are fine & i do fortnightly water changes of 30%.

Any advice or help appreciated x

 

[Assaye]

Wow . . .

Check our filter. Fish have been known to get sucked up/swim into filters. Not sure about the damage to the tails and corys though.

 

[DizzyMoo]

Filter i've got is a fluval 3+ & a clearseal thing, cant remember the number but its powerful. I've found no dead fish in either

Thanks for the suggestion x

 

[eschaton]

You have live plants, so it's possible something snuck in on them. In the US, it's fairly common dragonfly larvae end up on plants, especially when they are cultivated outdoors. Dragonfly larvae are voracious predators of small fish - I think they wouldn't have a problem polishing off a smaller tetra. There are other insect larvae which can do much the same thing as well. Look around the tank for something brown and buglike crawling on the substrate or the plants.

 

[reeeedfish]

what kind of pleco is it? Some are carnivorous.

 

[DizzyMoo]

You have live plants, so it's possible something snuck in on them. In the US, it's fairly common dragonfly larvae end up on plants, especially when they are cultivated outdoors. Dragonfly larvae are voracious predators of small fish - I think they wouldn't have a problem polishing off a smaller tetra. There are other insect larvae which can do much the same thing as well. Look around the tank for something brown and buglike crawling on the substrate or the plants.

Ive been sat staring into this tank for that long my eyes have gone funny, When i get plants i do rinse them 1st for snails but i have noticed there are 2 snails in the tank. Both not even half the size of my little finger nail yet, 1 is a trumpet snail & the other i haven't a clue but i got rid of it soon as i found it as i didn't want over riding with them. I can't see anything else & i've moved filters, plants & all bogwood to see if anything was lurking but can't see anything else.

If it is something like you suggest are they of a size i would see clearly & how would i get rid?

I've even blamed the cat during a blonde moment til i remember she couldn't lift the lift or fit a paw through the 1 1/2 inch gap & then bend it to catch them all lol

Hmm far as i know its just your bog standard common plec, Paid £1.75 for him 5 mth ago ish.
He was in my 3ft til i'd found a 4ft then moved him into there. I didn't have tetras in the 3ft so i can't even say whether or not it happened then.

 

[eschaton]

Well, from what you said, it sounds like an issue of predation. Erosion of fins and fish missing could be a water quality issue, but if the tetras are missing tails entirely (as opposed to just missing the rays of the fins) than something is clipping them off. And honestly, none of your fish could possibly be killing that many tetras in a night. Eating them once they die, sure, but not killing them. Which makes a dragonfly larvae or something similar seems most likely. They can get fairly large - given their habits though, I'm guessing the larvae would have to be at least 50% larger than the tetras you keep

Do you have a top? I'm wondering if they all jumped somewhere behind the tank.

 

[DizzyMoo]

Yes its a solid wood hood, Quite heavy but all along the back does run a gap of about 1 1/2 inch max for the wires.
If you think they are bigger than the tetras then that has actually given me the serious creeps (I'm due a baby in 4wks & have a 4yr old) .
I can't see down behind the tank as it's to tall but i'll have a go on a stand chair tomorrow.
Would they of come in on the plants? How do i get rid if it is them?
Would i not see them at all? Are they nocturnal then.. I'm thinking leave the living room light on. Does a fly spray help if i covered the tank with a sheet.

Sorry for the questions but i want rid of them if its these.

 

[eschaton]

This link ought to give you some ideas what to look for.

 

[mbsqw1d]

Wow . . .

Check our filter. Fish have been known to get sucked up/swim into filters. Not sure about the damage to the tails and corys though.

yep. was panic stricken last night when I spotted half a Cory sticking out of the side of my Fluval 4+!!! Wasn't moving, I thought it had ripped his back end off. Quickly unplugged it and casually out he swam. The little #29###!

Please watch your language. This is a family forum!

 

[Assaye]

Wow . . .

Check our filter. Fish have been known to get sucked up/swim into filters. Not sure about the damage to the tails and corys though.

yep. was panic stricken last night when I spotted half a Cory sticking out of the side of my Fluval 4+!!! Wasn't moving, I thought it had ripped his back end off. Quickly unplugged it and casually out he swam. The little #29###!

Somewhat ironicly, after posting that, I awoke to find two neon tetra and my peppered cory stuck in the filter. None of them survived.

 

[Davo86]

What species of tetra are they?

 

[DizzyMoo]

Neon tetras, I managed to "carefully" peer over the tank by standing on a chair & there isn't anything other than a fiver & some fluff down the back lol. I couldn't see anything crawling or any gaps for something to be hiding, Grabbed a stick anyway & poked about but nothing came to greet me.

Well yesterday evening for 2 hours before i went to bed i decided to turn the tank light off whilst i was in the living room & see if i could see anything whilst it was dark, but nope. Then after the 2 hours i turned the light on to find 2 more tetras missing!!
Even if they were suicidal & jumping out the back surely i'd see a bunch of dead fish behind the tank, Or start to smell them? I do have a cat but she cant fit behind the tank to enjoy them either.

So now i'm down to 3 tetras!! I seriously don't get this.

Shall i completely drain the 4ft tank down to the sand, remove all plants & wood & see if that gives me any clues?

 

[DizzyMoo]

This link ought to give you some ideas what to look for.

Thanks,
I'd been checking out dobson fly yesterday on the internet & they knock me sick i can not stand little bugs,insects & the likes. I can't see anything remotely like that anywhere, but i'm in 2 minds to chuck out all the plants & start a fresh by as i said above emptying the tank & starting again.

Would this be a start?

Thanks x

 

[DizzyMoo]

I've now moved all fish into my spare 3ft tank, & drained the 4ft down to the sand substrate, Tomorrow i will start investigating behind it although from looking i couldn't see anything. I've 3 tetras left so if by morning i still have 3 left then woop, but if any are missing then i give up *sigh*