neons disappearing very quickly

[Dred]

Hi hope everyone had a good xmas.
Here's a question for you.

At the weekend I purchased two red swordtails (one male and one female) and ten neon tetras to add to my tank. I already have eight black widows, two peppered cories, two leopard corries and a spotted raphael catfish.

All tank results are ok - ammonia 0, nitrite 0, nitrate 12.5mg, pH 8.5 (our tapewater is 8.5).

We have only two neons left! The male red swordtail has also gone into hiding (he spends most of the day under a rock). I have found a couple of dead corpses in the tank, one lying on the bottom with no tail, and one floating with a huge chunk out of it's belly.

I think something is going on after dark!! Does anyone know if this is likely to be the swordtails or my black widows? The black widows do seem quite aggessive, they will chase anything off the algae flakes I drop in for the corries and plec (as long as the plec isn't sitting on it!).

I loved the little neons, I can't think that there was anything wrong with them as they were all so lively.

 

[Alurny]

Im not sure have you looked in all hiding places? Sounds like the swordtail may be protecting eggs but im not sure if so he would ne quite agressive. Im not really up on alot of this.

 

[SirMinion]

Depending on it's size, i'd point the finger at the raphael. They're opportunistic night feeders and become preditory if hungry.

 

[ddm18]

Another possibility: I've heard of plecs eating neon tetras, because they rest near the bottom at night.

Lots of people insist that plecs are completely herbivorous and won't eat fish, but I once witnessed a common plec eating a (previously) perfectly healthy cory, so can vouch for the fact that they will!

 

[littlefishie]

Im not sure have you looked in all hiding places? Sounds like the swordtail may be protecting eggs but im not sure if so he would ne quite agressive. Im not really up on alot of this.

Aren't swordtails livebearers?

Check your filter. I've had neons disappear into those before.

 

[Blackhawksfn0286]

The protecting egg part i am not very sure cause the swordtails are livebearers... how long ha the tank been goin... Neons don't doi well in new tanks...

 

[SirMinion]

Lots of people insist that plecs are completely herbivorous

Certainly not! In fact there are more plecs that are omnivorous or carnivorous than there are herbivorus species.

Plecs will eat anything they can attatch too, but I would still doubt that they could catch a healthy tetra, even when sleeping.

 

[Dred]

Hi all, thanks for the feedback.

The tank has been up and running about 4 months and water tests have all been good for a long time. I still like to do a 25% water change each week.

We did have dropsy a number of weeks ago, introduced I think from some poor quality guppies. We lost the male and four females over about two weeks followed by one of our black widows who had previously been very healthy. We treated with aquarium salt and Myxazin and all has been well since. Could there be traces of salt still remaining? We have done a number of water changes and all other fish seem healthy. Having said that our male swordtail does swim a little strangely every now and then. Instead of propelling himself with his tail, he bends in the middle with his head and tail moving from side to side in the same direction. Is this part of some strange mating ritual? )

Just a quick update. I've checked the tank really closely and found two neon bodies. Both have their tail fin completely gone but no other marks. Could our Black widows be turning into fin nippers? Would this cause the neons so much distress that they would give up and die? I think that it's the black widows as one of the guppies was attacked and this was before the swordtails were introduced. Or was it our plec? I could do with Sherlock Holmes on the case!!

 

[sylvia]

I think it's the raphael cat - I doubt it's the swordtails, obviously not the cories, don't think it'd be the plec. The black widows are known to be fin nippers but neons don't realy have much in the way of fins - nothing long and flowing - and it wouldn't out-right kill them. Have you considered they may be sick and being eaten AFTER death? I know you said they looked lively but neons are sensitive fish.

 

[Dred]

Thanks for the reply.
Not sure what to look out for in terms of sickness in neons. They are lively and eating well, no signs of fungus or bacteria or white spot or anything.
Could they be stressed, and would this kill them? The black widows do seem a little aggressive, they remind me of piranas at feeding time and the mafia at all other times.
I am getting tempted to take these fin nippers back to the store where I bought them.

 

[sylvia]

Stress wouldn't directly kill them I don't think but it could make them susceptible to disease. It could be internal parasites though - stringy poo. You may not notice this until it's too late you see.

 

[mwm]

Im ganna to say its the raphael cat too. My friend has 3 of these guys in his 90g and they will eat anything including shrimp chunks so im guessing they would go for a neon

 

[Talleyrand]

Neons are just the punching bags of the fish world
Neons sometimes "sleep" motionless on the bottom of the tank which makes these already slow little fish a prime target for abuse.
I dont even try to keep them anymore.

 

[Dwarfs]

I say it's the rafael cat

 

[Dred]

Thanks Guys
I guess I'm gonna have to resign myself to the fact that my beautiful raphael is a night feeding murderer, so no more neons until I buy another tank for my daughter.

Oh no!! I've just looked in my tank and my beautiful male swordtail is lying on the bottom on his side. He's dead.

I can't understand what's going on. Am I just really unlucky in the fish I buy or is something in my tank causing these problems? I can't believe it's the tank, all our water parameters are spot on and I don't overfeed and I do water changes regularly.

Any ideas what was wrong with him. I think it might have been a swimbladder problem. We got him about a week ago and all seemed fine to begin with, right up until the end he was feeding OK. A couple of days ago he started swimming strangely. He was bending in the middle of his body and his tail and head were moving from side to side in the same direction at the same time. Sometimes he would sit motionless on the bottom of the tank or under one particular rock, sort or wedged in.

Do you think he was ill when I got him? All the rest of our established fish seem OK (8 black widows, 4 corries, 1 raphael catfish).