Dying Tetras

[JellyPi3]

I did have 5 cardinal tetras, until recently when 2 died and 1 is kind of dieing.
It is swimming to the surface and gasping for oxygen, which made me think the oxygen is low, but the other two are fine swimming nearer the bottom, and my fighter and pleco are doing perfect.
I have plants, but one of the plants looked a bit dead so i removed it.
I know this fish is going to die, but i just wanted opinions on whether the other two are going to die.
They seem perfectly fine, but then they all seemed fine the other day.
It could be that i had a bit of a faulty batch, i don't know.
Any ideas would be appreciated x

 

[Miss Wiggle]

can you give us some more info on your tank, what size it is, what equipment you have set up, what fish you have in there and what your water test reults are

 

[JellyPi3]

the tank is 54L
i have 1 fighter in there are 3 cardianals, and a bristle nose pleco.
i have a 50w heater and a filter, not sure what sort but its in perfect working condition.
not sure if that helps.
ill get the water results tonight, im out of test strips atm.

 

[Miss Wiggle]

how long has the tank been set up for? how did you cycle the tank?

have you made any changes to the fish's diet or environemtn, added any new ornaments or anything like that?

if you're going for more test kits tonight, invest some money in a liquid test kit. they're significantly more accurate than the test strips, unfortunately results from test strips are not worth the paper they are written on.

 

[JellyPi3]

I have only had the tank for a few days, but it was set up for 3 or 4 years before me. The fish that were in there have been rehomed. I was told if i kept the filter in tank water, then it would not need to be cycled. I did get new gravel for it, becasue the gravel in it was filthy (the tank had not been cleaned for a year).
I put the fish in the day i got the tank. I was told it did not need to be cycled. Im guessing that is my problem.

 

[Miss Wiggle]

could be, let me make sure i've got this absolutely straight before we say what happened.

when you bought thte tank, did it come with fish?

 

[JellyPi3]

i went to a friends house, and in the tank they had a shark the length of the tank, an angel fish and a gourami. All way to big to be in a tank of that size. So i offered to take it from them, and rehomed the fish. i cleanred the tank, without chemicals, just with water, filled it, heated it ect. and then put the fish i bought from a shop into it (the tetras, betta, pleco)

 

[Miss Wiggle]

so the tank was wtihout fish for say max 12 hrs or so?

when you cleaned the tank, did you clean the filter media at all and if so did you do it in tank water or under the tap?

 

[JellyPi3]

yeah, max about 5 hours i'd say
i put the sponge in tank water from the filter, to keep it going. i cleaned all the boxy bits cos it was clogged with algae. i then put the sponge in tap water for like a minute then put it in the tnk with the fresh water

 

[hollyp0p]

did you treat the water to make it safe for the fish?

 

[TribeOfShroom]

i then put the sponge in tap water for like a minute then put it in the tnk with the fresh water

I'll probably be jumped on for saying this, but I think thats you're problem. Chlorine will kill the benefical bacteria on your filter sponges. If you didn't dechlorinate the water before putting the sponges in, then you've most likely wiped out the bacterial colony.

Which means... you're starting a new cycle.

 

[JellyPi3]

yeah i used tap safe, and i did a water change at one point becasue the gravel i used had a bit of dust of it (i did wash it b4 you ask, there was a bit of residue left on the collinder)
so i did a 50% water change and treated that water too, making sure its safe for them

damn, so you think the other two fish will die as well, the betta looks ok except it keeps swimming about madly, and the pleco is seemingly fine. any suggestions or should i just wing it

 

[TribeOfShroom]

If you used tap safe (i'm guessing it's a dechlorinater) then your filter sponge should be ok, but until you can test your water and post the results. We won't have a clear picture of what's happening

 

[JellyPi3]

ok thank you for the advice. ill post the water results asap.

*btw i didn't put the taop safe in the water i put the sponge in, so i'm guessing thats the answer.

 

[TribeOfShroom]

ok thank you for the advice. ill post the water results asap.

*btw i didn't put the taop safe in the water i put the sponge in, so i'm guessing thats the answer.

Doh!! That'll most probably be it then. Get yourself a liquid test kit asap! and start monitering your water stats. Looks like you maybe doing a fish in cycle.

Good luck There are some excellent threads on here on how to do a fish in cycle, so don't worry, you're not alone