Thanks bro LaW for the info.
For (1), I Goggle for "tank connector" & found below pic. Is this right?
Size wise, I plan to purchase AquaBee2000 pump for this project but not sure what size connector can fit nicely onto an AquaBee2000 pump inlet nozzle. Hoping some bros & sis on the forum who's familiar with this pump can advise me.
For (2), I'll be happy as long as it dosen't leak.
For (3), once I figure out the exact connector to use in item (1) above, I can probably get this problem solved too.
For (4), ok, I shall make sure the connector to use in item (1) above can fit over an 8mm baffle.