New fish keep dying

[rjdoghouse]

I am having problems with new fish in my tank - they keep dying!


I have a 20 gallon tank, and until two days ago there was live hornwort in it. I took it out as it wasn't doing well and making a mess of the tank. There are no other live plants.

My water measurements I don't have. I went to the local shop and they did a full test of my water last night and told me that the water tested perfect, there is nothing that they can see. They didn't give me the numbers, though. I have a ph test kit and a nitrite test kit at home and the levels have remained constant at ph 7 and nitrite under 0.3 ( it is a tinge of pink, but not enough to match the .3 colour on the sheet that came with the test.)
I had thought there might be a spike, but nothing has tested for that.

I did do a water change about a week and a half ago - 1/4 of the tank, vacuuming up the waste from the dying plant. I use Pro aquatics water conditioner and Pro aquatics bacteria starter when I change the water. I also added the bacteria started to the filter when I added new fish.


I have 5 baby swordtails, 1 head and tail light tetra, and four cory catfish in the tank. I had an older male betta but he died about 3 1/2 weeks ago. He was about 3 or 4 years old, so I'm assuming it was old age, but maybe that was from whatever is going on with my tank.

I purchased 5 teeny neon tetras 1 week ago, and moved a young healthy male betta into the 20 gallon tank. Within 3 days all of the new fish were dead. I tested the water with my two tests and it tested 7 ph, and under .3 nitrite. I wondered if it was stress, so I waited 2 days and then purchased 2 neons and one betta. The betta died within two days. The neons are still around - I purchased them on Thursday the 16th of January. One of my catfish is acting a little listless, but if I touch the tank near him, he will swim about again.

I am not sure what to think. My adult swordtails died about 3 months ago - and I lost quite a few fish at that time. I only have the two tests and they had the same results. I change the water only about once every 3 or 4 weeks, have an outside filter (aquaclear) and never change more than one of the three stratas at a time. I rinsed the foam out when I did the last water change as it was quite clogged up from the dead plant material.

Could I have a bacteria problems or some kind of disease? Any ideas would be great. I am afraid to add anything to this tank as I don't want to kill any more fish. I feel guilty enough already!

 

[William]

I'd reckon its poor water quality in your tank. Have you added anything else to the water recently? Have your water company added anything to the water?

From what it sounds like your betta died from old age and then these new fish, when they arrived in your tank the shock perhaps of PH or water conditions which your other fish have grown accustomed to.

I would change the water more often - weekly or fortnightly is best.

You mention bacteria and disease, did the fish have any marks or wounds on them when they died?

If you are sure your ammonia nitrAte and nitrIte are ok, test at the shop or its probably more economical in the long term to buy your own. If they show the readings are all ok then I would recommend perhaps cardinal tetras instead of neons.

 

[William]

I rinsed the foam out when I did the last water change as it was quite clogged up from the dead plant material.

Wow just read this! This probably explains a lot! The filter foam is the habitat for almost all the bacteria (70% ++) and so, by rinsing it - if you did it under a tap which it sounds like you will have removed/killed the huge colonies that have built up over months. I find my filter foam rarely needs cleaning and when it does I always rinse it out in tank water from the tank, in a bucket. The water in the bucket will get very dirty and that can be thrown away. Also never keep the foam out of the filter for more than about 20-30minutes.

Also saw you add bacteria starter on every water change - its debatable whether it has ANY actual benefits and certainly in an already cycled tank it will do nothing for the water. It'll also save you quite a bit of money.

Thats about all I can think of hopefully someone else can help if I missed anything.

Also - you can try - to post your plant problems in the "How does your garden grow" section. Rose our plant guru and others will no doubt have your tank a jungle in no time

Welcome to the forum

 

[mikebarg]

I would suggest you really clean out as much of the dead plant matter in the tank as you can find. Any type of decaying organic matter can cause problems in the aquarium. I wouldn't add any more fish. I'm not sure what you have left in the aquarium now. Try smelling the water. Does it smell bad. If it does it is bad. It should smell like wet dirt. Try taking the handle of a fish net and stirring the surface of the water rapidly to make some bubbles. If the bubbles do not pop within 30 seconds you have a water problem. When I have water quality problems I reduce feeding and do 20% water changes daily until I can resolve it.
The other thing I would ask is have you put anything in the aquarium that was not specifically designed to be in an aquarium(rocks,orniments, ect). Sometimes these types of thing leach chenicals into the water that are harmfull to fish.Hang in there!

 

[catman]

Also, it might be worth investing in a better test kit..

The minimum i would test would be ph, ammonia, nitrite and possibly nitrate at least once a week.

What temp is your tank kept at?

Other than that up your water changes...