Ok to start im a new fish keeper, i have 10 fish all of which are fine except for my oldest goldfish that came with the tank, the tank was in disuse and this little guy survived a full year with a neon tetra that i had to remove when filter pump was turned back on as it didn't have the strength to fight the current.

This goldfish is smaller and lighter in color than the one i've bought myself, i think that it may have an infection in its tail fin, not sure worried about my koi and minnows mostly.

Any help is appreciated.

PS. I've included a picture of the overall tank unsure fo the actual size so i used a standard size poker card and a reference in-case it helps.

Hi pearce135,

Firstly welcome to the forum and to the hobby of fishkeeping.

I'm not an expert in goldfish/koi or coldwater fish at all, but I'm sure one of the experts will come on here soon to help you.

However a few questions:

How long have you had the other fish for/Have you just introduced them?
Have you done any tests on your water?
Have you had the tank from new or was it give to you along with the goldfish (I'm looking at the age of the fish here but I'm not sure how long they live for to be honest!)?

thank you, for the welcome and reply.

the goldfish in question is around 3 the tank was given to me by my cosin who got it off my father, he let it get really bad i had to spend 4 hours cleaning it and the filter was clogged, i cleaned the tank and let it run for a week before reintroducing my neon and goldfish (at the time the only two i owned) the neon struggled and had to be removed its in a bowl i gave to my little brother and it is fine, the new fish were not introduced for a fortnight after this, the koi, minnows and new goldfish have been thriving and ive had for around 3 weeks ive already seen a little growth in some of the minnows.

im a novice so im going by what i read atm, but i have preformed a Ph test and was going to do an ammonia test.
the ph level was around 7-8, i was using a litmus test so was going by a chart i got.

the goldfish in question seems to be energetic enough, and i did notice that it had torn its tail fin, this may be a result of the koi they often brush against each other and the goldfish.

im not sure if this is what the healing is suposed to look like or it is infected.

I'm not sure if you have uploaded pics, if you have sorry I can't see them, probably down the work pc's being locked down security wise.

You said you've done an Ammonia test, what was the result?

As your other fish seem to be thriving the water conditions may not be the cause. It may well have an infection somehow and may have lost colour due to stress or whatever. I'm not going to start suggesting treatments as like I said before I'm not experience with coldwater at all.

The only suggestion I could make to you in the mean time is to possibly put the poor thing in a hospital tank (if you have one or could set one up) so that it gets some peace and quiet to heal etc (helps with medicial treatment as well as you are only treating the one fish).

Hopefully someone with a bit more experience of coldies will be on to give you better advice.

sorry the amonia test was a typo i edited it, i am going to do one soon i have to wait a week for my pet shops next delivery they were all out when i was last up to get supply's for my other pets, on the hospital tank would you suggest a fishbowl or something of that size as i dont have that many fish and they are relatively cheap, i had a spare bowl but its home to the neon tetra now and i gave it to my little brother.

In that case I'd leave him were he is. Personally I'd never suggest a fish bowl for anything but pot pouri or candles as they are far to small and don't have filtration.

You may already know this, so sorry for teaching you to suck eggs if you do, but all fish tanks should have filters regardless of whether they are coldwater, tropical or marine. This due to what is called the nitrogen cycle.

A basic explanation of the nitrogen cycle:

* Fish waste, uneaten food etc produces ammonia which is deadly to fish.
* Bacteria turn this ammonia into Nitrite which is also bad for fish.
* Another type of bacteria turns Nitrite into Nitrate which isn't so bad for fish as long as it's not too high.

Your filter helps cultivate this good bacteria in the filter media (sponges etc) that you have.

Their are some good articles on FK listed in the below link which will go into more detail about this and will aid you as you learn more about fishkeeping

Beginner Articles

My beginner tips that I wish I had been told when I started many years ago:

1. Research the hobby, your fish, the fish you want etc. I can't stress enough how important this is. The internet is a fantastic tool for this. Also don't just rely on one source of information. Some sources may differ with there advice from others.
2. The care of the fish come first! If it's not compatible with your tank size, tank mates or water conditions then it's not for you.
3. Buy yourself a decent test kit. Ammonia, Nitrite, Nitrate, pH are a minimum
4. Do not clean filter media with tap water. The chlorine in it will kill of all the good bacteria mentioned above. Filter media should be cleaned in tank water (remove the tank water first, don't clean it in the tank!)
5. Do some more research!

Another bit of advice, get some sleep!

My excuse for being up at this hour is I am working (well attending, not really working!), what's yours???

thanks for the help :)

i do know about the nitrate levels, i found it out when my tank turned cloudy for a bit when it was just the neon and one goldfish, i looked into it and it settled in a short while, i read up on it and apparently that was the bacteria kicking in as it were.

i looked into quite a bit before i got the species of fish i did i made sure that they were all school fish where friendly and had similar diets.
i do a bit of a water change once a fortnight just to help keep ammonia levels down.

i didnt know that it was the chlorine in the water that killed the bacteria, so i know to watch out for that.

i knew some of this stuff from before because when i was going to get the tank i had planed on getting an axolotl but couldnt find a local place that sold them.

they have simular upkeep needs, still its awesome to have a place to get help when i need it :D

I just get random bouts of insomnia lol so i play or create games when it happens lol

I've only been on here a shortwhile myself butI used to be a mod on another forum that shutdown ages ago (not because I was a mod! )

From the experience I've had and reading other peoples threads on here, FK seems to be the place to be for good advice.

Keep us all up to date with how you're getting on and we all love pics too.

Take it easy mate