Canister for sand.
HOBs will jam with sand. The fish just has to rough house to kick sand way up high. then it's RACKITY RACK noise for the whole day.
HOBs have the impeller directly exposed to the intake.
Problem when bichirs freak and kick sand way up into the tank.
Canisters protect the impeller after all the filtering. Such as an Eheim 2217. Impeller is protected by the entire foam filter and biofilter, so sand won't reach it.
HOBs will jam with sand. The fish just has to rough house to kick sand way up high. then it's RACKITY RACK noise for the whole day.
HOBs have the impeller directly exposed to the intake.
Problem when bichirs freak and kick sand way up into the tank.
Canisters protect the impeller after all the filtering. Such as an Eheim 2217. Impeller is protected by the entire foam filter and biofilter, so sand won't reach it.