Goldfish optimum temperatures...

Question
QUESTION: I have a 55 gallon goldfidh tank, containing three goldfish, the largest about five inches long not including the tail, a spotted dojo loach and a clown pleco.  Recently, one by one, each of my goldfish died.  The first two had no symptoms except general lethargy about the day before they died.   The last one lived about three weeks longer, but had a strange, thick, tumor-like growth on the top of her head. As time progressed, she got another, large red sore spot under her throat that looked nothing like the first growth.  Finally she lost her appetite and died. The dojo and the clown pleco are fine. Throughout this time, I treated the tank by raising the salt content in an attempt to kill off the disease.  I have a lot of experience keeping fish but have never seen anything like this.  I'm looking for ideas as to what this could be, as well as any extra advice you have for starting over.  I plan to drain the water and replace the carbon cartridges, keeping the old biowheels for the bacteria.  Any advice or ideas as to what killed my fish would be greatly appreciated!
ANSWER: Hi!

First off....if you had a dojo loach and a clown pleco in the tank then the tank had to be heated right, cause those two fish are tropicals and need a heated tank.

So if your tank was heated, thats your problem right there, goldfish are coldwater fish and should not be mixed with tropicals. I think that if your tank is heated, then this is why your goldfish died and if it is then you don't need to drain your tank and start again just keep fish that go together and have the same water requirements.

Hope this helps!

Cheers! Rach

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

QUESTION: There's no way the goldfish died because the tank was heated.  The tank is heated, but it never goes more than 73 degrees, and I have had all of the fish for at least five years, with no problems until now. There have been no changes in water condition or quality or any conditions of the tank. I guess thats about it, any other ideas?
ANSWER: Hiya!

Well if you don't think that is a problem to keep goldfish in a heated tank, that is your choice and thats fine but it's not the optimum conditions for them as they are coldwater fish and even 73 maybe too warm for them. And just because you have had no problems for the past 5 years doesnt mean an accumulative effect hasn't been building to cause their death in those 5 years.

My only other suggestion if you say you have had them for 5 years is that they simply died of natural circumstances. If there has been no changes in water conditions etc there is really no other explanation for it.

Sorry I can't be more help!

Cheers! Rach

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

QUESTION: I am curious if your statement of goldfish being intolerant of warmer waters has any basis or is just opinion.  Even a simple google search will show that goldfish originate from temperate climates with seasonal variations in temperature from near freezing to very warm (nearing 80 degrees and the level at which oxygen begins to rapidly loose solubility in water).  This is why they make great pond fish...Please clarify why you think the symptoms might have resulted from temperature instead of some unknown disease or fungus/parasite, this seems the more likely cause to me.  Yes at warmer temperatures, it is easier to grow harmful and beneficial bacteria alike, but it still does not explain why a stable, unchanged tank would go south so quick.  Before questioning the temperature, i would have questioned the method of treatment and maybe suggested that next time, a more radical, powerful anti fungi, parasite, or bacterial medication is dosed in quarantine.  Maybe ask for some pictures next time for identification instead of shooting in the dark?

You do not sound like an "expert" at all, or at least one with any formal educational background in the field.  

Brian

Answer
Sigh.....I didn't realise that to be an 'expert' on AllExperts you had  to have a 'formal educational background'. At the end of the day, the moderators of this site deemed me qualified enough to answer questions, so maybe you should take it up with them and not me eh?

As for making great pond fish....there are goldfish such as Nymphs and Fantails etc and then there are Comets and Comets are the ones usually recommended for ponds as they are hardier for fluctuations on temperatures, the standard Goldfish however are not as hardy.

As for medicating, I think too often people are too quick to just chuck medication into a tank and hope for the best but that IS just MY opinion, if I am allowed to have one that is.

As  already stated to Lindsey, I volunteer my time here, so if I am unable to answer a question I apologise but if Lindsey wasn't happy with my answer the first time, why come back for a second go, maybe Lindsey should have diverted her attention to a 'true' expert like you eh...?

In all the question I have answered, this is the only negative feedback I have received but it's been enough to consider withdrawing my time...