Please Help - Sick Goldies

Hi All,

We are having a problem with our tank and goldies, any help and advice is appreciated.

We started off with a small tank with 3 Comets, this tank was running successfully for +- 10 months. A month ago we bought a 20 gallon tank and started cycling the tank for 2 weeks.

After the 2 weeks we introduced the Comets and the Amazon Swords we already had. They were doing very well and were on their own in the tank for about a week.

We then introduced 2 Red Fantails and 2 Bristol Shubunkins. The smaller of the Shubunkins looked ill and we transferred it to a hospital tank. The Shubunkin died 2 days later. Since then we have introduced more Comets and Fantail Calicos.

We had 11 fish in the tank and 3 have died in the last 2 weeks. The fish that died were 2 Shubunkins and a Fantail Calico. The symptoms displayed were lethargy and the fish were swimming lopsided.

The fish would then just lie at the bottom of the tank barely moving and a day or 2 later would die. Now the remainder of the fish are lethargic and lying at the bottom of the tank. It appears that the one large Comet has developed a red ulcer on the side of its mouth. It is still eating normally and swimming around like usual.

We have done a 50% water change and medicated with Tetra GeneralTonic. We have also added a second box filter with activated carbon in addition to the box filter and the undergravel filter already in the tank.

There are 5 Amazon Swords in tank at the moment.


Any advice would be appreciated.

Thank you

Christelle and Ian

 

Your problem probably is that the tank is over stocked. Goldfish are dirty fish, meaning that they in other words "poop alot". For a 20 gallon i would have 5-6 goldfish max. as they can grow fast and the larger they are the more "Poop" they make. I believe that the tank is unable to convert the ammonia into nitrite then into nitrate fast enough. AKA Too small tank for such high bioload. Also, so you have any airstones running in tank? Sometimes your O2 levels drop and you never expect it. And Boom, dead fish :-/
Welcome to 3reef

 

Swim bladder infections come from having the swim bladder blocked off from intestines. It would take the fish a week or two to die. My neighbors pond had a foot long shubunkin live for a month on its side. It would swim up and eat sideways. My guess is that there isnt enough o2 or too much fish :-/

 

Thanks for the quick reply and the advice everyone.

Here is some more info if that helps.

Just to check my maths, the tank is a 100 liter tank (90cm x 32cm x 37cm).

When we first setup the tank we treated the water with tetra aqua safe and easy balance. and then we left the tank and filters running for two weeks (we transfered filter media from the old tank to the new one to get the bacteria started).

The fish average in size between 1 inch and 3 inches.

We are in South Africa.

we are using sera dipsticks for testing.

NO3 25mg/l
NO2 5mg/l
GH>10 d
KH 6 d
ph 7.2

No Heater

Aeartion: 2 airstones + under gravel filters airstone

Water change 20% every week

tank size: 90cm x 32cm x 37cm

the tank has been running for about 5 weeks

filtration: 2 X corner box filters with activated carbon and filter floss
1x under gravel filer with one lift pipe.

tetra easy balance is added every time we do a water change.

we feed everyday once with flakes

we have 5 amazon swords

Unusual findings on the Goldfish:
one has a ulcer by its mouth

Unusual behavior:
lethargic, some are swimming lopsided and sideways, lying on the bottom


Medications/what has been tried or done do far:
Tetra General tonic, only put in today so nothing we can see.

thanks again for the help

 

If you have this you probably are overstocked :-/

 

I agree on the overstocking. Also for that many fish an undergravel filter is not enough. Add a HOB filter that has a rating for at least 40gallons. Alot of diseases can be avoided by not overstocking and by great filtration. Good luck.

 

Sorry to hear about your troubles. I agree with all of the above and would add a comment to keep an eye on your water temperatures. In my experience, goldfish have always done better in cooler waters. I'm glad to see that you're not using a heater, but I'm curious as to what your water temperature is. I ended up moving my goldfish to a separate tank than my other freshwater fish (swordtails and platies included) just so I could keep the tank at room temperature (which is around 69F for me up here in North America).
Good luck!