Your intake only needs to be halfway to three quarters of the way down into the tank. It should not be all the way to the bottom because it is too easy to pull in gravel or sand, which is not good for the filter. Also, if any particles make it that far, it is a sign of serious overfeeding. If you do buy the extension, yes, you need the mid-level and you will most likely need to cut the extension down to fit.
Date published: 2017-01-16