Pre-quarantined fish for sale?

[marrone]

1. Unstable!, If there is no biological filtration and you are merely controlling Ammonia, nitrite ph etc, through water changes, even if frequent and large there will constant fluctuations in water parameters, and I would imagine this is very stressful.
Quick thought: Would you trust putting an expensive angel fish in a display tank that isnt established but held together by frequent 50-100% w/c's, probably not, so why is this different?

The tank wouldn't be unstable, unless you load it with fish and feed like crazy. The tank would be stable enough, with water changes and vacuuming out left over food and waste, to keep everything stable enough to QT a fish for a couple of weeks. You need to watch your fish instead of consistently testing the water. It's not that hard to do.

In your example back off on the cost of the fish, because that shouldn't matter if the fish is expense or not. There isn't any reason you wouldn't or couldn't place any fish in a QT where water conditions are controlled by doing water changes, limiting the amount of fish and the amount of feeding.

2. Medication, Of course only after a symtoms surfaces, this will then kill bio-filter, so if your tank is self controlled (bio filtration) then you have to go back to manual control (WC's every day, or very frequent)

Once again you don't need to use biological filtration, just a bare bottom tank with water movement. You can then start to treat with medication. If you plan on using some sort of biological filtration the copper or medication will not kill all of it just some of it. You may have to do a water change until it's fully back and functioning.

3.Unatural, although the lack of competition and agression will reduce stress, wont an extremly unnatural enviornment cause stress? no sand for wrasses, no rocks to graze for tangs, just pvc and glass, i think this may add to stress, no room to swim (even with the largest QT's what are they 50 gallons? for a large naso or angel thats like solitary confinement)

Your main tank is also a unnatural environment and does cause stress too. You are setting up a QT to see if your fish has some sort of disease and also giving it some down time. There is going to be some stress, just like you have stress in your main tank, regardless of the size of the main tank.

A QT is for protecting your fish in your main tank first and your new acquisition second. Setting up a QT isn't that hard to do. You need to monitor it and make sure you remove all the waste. The bigger the better, as it will take time for the water to turn bad, and water changes are needed. In some case you can change all the water, clean the tank, and then drip the fish back into the new tank.

 

[JLAudio]

Marrone, I hear your point and have heard it and read it from every experienced fish keeper I have spoke to. However my personal failure at this, even with following your protocol to the tee, makes me a non believer. I have taken fish from my main tank that are actively swimming and eating with a sign of ich, put them in a hospital tank and their dead by morning. Obviously the cause of death could be debated, however I often find that the fish has a much better chance in the main tank than a QT.

In regards to the un-natural aspect of a QT in comparison to a display, I think we have all experienced fish that fair better when aspects of their natural habitat are considered (jawfish,wrasse/sand bed etc.). Although nature will never be duplicated I do believe providing these considerations relieves stress

In ragards to the Cost of fish as a factor, although we may not admit it, it does add to a fish loss when it costs more $$$. I know ethically all fish deserve the same consideration, however I have seen damsils used as feeder fish but cant say ive ever seen a mystery wrasse used or another small/expensive marine fish. Doesnt the damsel have the same value of life? However, its cheaper and therefore acceptable. I hate seeing any fish die, but if I would imagine that cost is a factor in the value of the loss of a new fish. OF course many exceptions, length of time having fish, fish personality, coloring, rarity etc. it is still a sad but true factor