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Fish/Goldfish creating a bubble nest?


QUESTION: Hi there,
Our family recently acquired a goldfish at a carnival several weeks ago (we had never had a fish before).  A local pet store set us up with a 4 gallon tank and some instructions (ie. adding water conditioner & salt and to feed only once a day). They told us we don't need a filter at this time (but if we wished to have one we would only have to do water changes once a week).   We are still learning the ropes.  We've done two 25% water changes every 4 days (and adding back 25% of the salt & conditioner).  We've noticed that the fish has been creating some sort of bubble nest in one of the upper corners of the tank.  Why is it doing this (I've read that male betta fish do this for mating purposes, but goldfish do not).  Am I doing something wrong?  

Thanks so much for your time and help!!

ANSWER: I've got some good news and some bad news.

The good news is you are trying really hard to make things right for this goldfish but unfortunately the tank size is too small and the pet store is feeding you incorrect information.

Goldfish won at carnivals are comet/common goldfish which can get 2 feet in size in less then a year. They need a spacious aquarium of 75g + with double filtration. A pond is better suited to these massive pooping large critters.

In a small tank size ammonia will build up, burning off the gills partially or entirely, and the stress of being in a small confined space will bring on disease. If you don't have a filter this is even worse.

Salt should never be used, Aquarium Salt, is a tonic for sick fish with funguses. If you think about, why would freshwater fish need salt after surviving thousands and thousands of years with fresh? It doesn't do all the miracle things it says on the bag it just helps cure some specific diseases. It often irritates fish.

As for bubbles, it could be anything, did you use soap? Soap shouldn't be used in the aquarium if you don't already know. It could be the conditioner used in a small tank, are you overdosing?

I would either donate him to a local pond, with the owner's permission, or to the pet-store.

Sorry that you got such misinformation, living creatures should never be presents or prizes.

- Ash

---------- FOLLOW-UP ----------

QUESTION: Hi there Ash,
Thanks so very much for your thoughtful reply. I am just sad that there is such misinformation out there.  Truthfully I'm not 100% this is a goldfish - it's more red and has long flowing fins.  In any case, I don't want it to get sick.  I have done the water changes - the water seems fine for a few days, but the fish just sometimes wants to hang out at the top of the water and seems to create these bubble 'pockets' in the top corner of the tank.  It's hard to say what it is.  I don't use soap at all (the pet shop warned me about that). Perhaps since I haven't used gloves to clean the tank or when I feed it, it is getting some of the residue from my hands?   I am not able to get such a large tank at this moment - but will hopefully get a better life for this fish.

He could be very well a red fantail (species of comet) Goldfish. Does he have barbels on or near his lips? This could identify him as a Koi.

If you can, could you possibly buy him an pump + airstone which would increase flow and oxygen? Since the goldie is a large creature and in a smaller environment he could be running out of oxygen. Most fish suck at the surface or 'exhale' when they are oxygen depleted.

Usually, gloves are unnecessary, (I only use gloves when handling my larger fish who bite!), just wash you hands or run them under hot water (as much as you can tolerate) without soap to wash off any congealed oils, food particles or whatever you have touched.

If you do run into any local ponds or have neighbors that have ponds don't be afraid to ask around to see if they will allow him to live there.  


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Ash WolFF


My knowledge of fish ranges from freshwater and saltwater fish compatibility and care from easy livebearers to monster fish. I can help you set up a simple freshwater aquarium to a complicated reef tank. I would be pleased to assist anyone who is new to the aquarium hobby.


I have been in the aquarium hobby for eight years mostly dealing with large and small aquariums. I keep mostly monster fish (Arowana's, Large Cichlids; Oscars, and freshwater/saltwater eels specifically) but now that I am in college I am keeping a 30 gallon tropical community and a 45 gallon brackish aquarium while my father tends to the big monsters I left behind.

I'm on YouTube! My 30 gallon community posts are the only ones that are up so far. My Brackish tank is next! I'm on Yahoo Answers:

I am currently in college aiming for a job in Marine Biology.

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