Most Eggcrate in the stores is 1/4" holes but if you do some digging around other stores, you may be able to find 1/8". This allows you to have smaller fish separated.
I think there are differing opinions on QT tanks because they are being used, IMO
, incorrectly. What we did:
A QT tank would be used for long term observation of a fish or bunch of fish so that IF someone needed to be medicated, they would be put into a hospital tank. QT tanks would be somewhat like your main tank with some decor because you want the fish in there to be comfortable and start acting and seeing "Normal."
In a hospital tank, it should be bare bones with nothing that would absorb medications ( gravel, rock, real coral decor) or would displace that much water that you might not medicate properly for the real amount of water on the tank. We just used PVC
pipe and connections only in a hospital tank.
So a QT tank is set up for long term, a hospital, set up for short time. In fact, our hospital tanks were set up the day we needed them as we kept water available to use all the time. They were taken down and stored when the fish were removed.
Hope this better clarifies.