Originally Posted by Mebbid
Bacterial diseases are incredibly rare and can be prevented with good water parameters.
Any parasites are too large to fit though a diatom filter. Both velvet and ich as well as others are too large for it.
I do understand about the treatment though.
I wasnt going to do it, but was just wondering what people thought about it.
It's not whether the diseases are rare or not, it's that the QT wouldn't serve a purpose anymore.
Even if you don't pass a long the parasites because of the diatom filter, and you have to move a fish to QT, you can't treat it.
It all comes down to a Chance really. If you buy a fish unaware of a bacteria it's carrying, and put it in the QT, your DT is doomed too.
If the QT isn't connected this isn't the problem.
It is possible to make a qt connected, but it'd just be more like an extra stabilized tank.
(I fixed your typos btw