ABout the only skimmer I know of that will fit on any of the pod type tanks is the Current USA Fission Skimmer. Is your tank a regular factory nano type tank with back wall and partitions or just a 24 gal tank? LOts of folks do not like the Fission Skimmer, but it does work, provided you keep a very close water level in the system. It does not take much variance in level to make the skimmer screwup, so a ATO is best to have....and then this potential problem is eliminated.