Just a side note to newer members or those thinking of joining. Beth and I have been on both the same side and opposite sides of the fence on many issues. What makes this site so great is that there are members who believe in what they post and try to present their views for others to consider. So I challenge all members to bring something to the table on the many issues posted on the various topics presented on the boards if they feel they are of value.
We do this site an injustice if we just sit on the sidelines for fear of debate
Sometimes too many opinions and general what-if discussions results in someone in crisis not knowing exactly what to do since they get a bunch of conflicting opinions rather than decisiveness and clear direction.
The thing for hobbyists to do is to set up a quarantine tank for in-coming fish so that they will never have a reason to introduce a parasite into their fish tank. However, when that is not done, and the hobbyist is dealing with a crisis, such as Meow is here, then the plan has to be tweaked. I recommend using the live sand because that sand has biological colonies on it which will help to kick start the biofilter in an uncycled QT and will aid maintaining a biofilter due to the surface space for colonies to grow on tiny grains of sand, as opposed to just a bare-bottom tank.
The chances of a fish exposed to ich not contaminating a QT, while the sand from a contaminated tank does is not very likely, and in my opinion doesn’t outweigh the benefits you get from the added live sand. What do you think happens to a QT when you bring fish home from the fish store and put it in the QT? You are going to introduce a parasite or a disease at some point. Introducing a pathogen to the QT rather than the display is the point for using a QT, right?
In Meow’s case, certainly she can use sand from another tank, which is likely a good idea since we don’t really know if the medication she put into the display in question caused the wipeout. Meow has said that she is going to do hypo on the goby. If that is the case, then hypo will kill ich on the fish and/or ich on the sand, or wherever it is. The goal is get a viable emergency tank up and running ASAP to treat a disease, not trying to keep the parasite you are going to treat anyway out of the tank.