Please Help In Filter Choice

[soundenzy]

i have three aquariums in my home.........20 g, 30 g, 55g
in my 30 i have live bearers........basically molly,platy........only foam filter.......now i wanna bye hob filter for all of my aq.....
but there is a problem........we have power cut problems in bangladesh (daily).......please suggest what can i do???
are there any hob that primes itself??? ...what will be the best filter for them.....basically priming is the biggest problem
please help

 

[mtv8dmarine]

The HOB filters I have sometimes will restart as long as the water level remains high enough but it's no guarantee and you may find a burned out motor as a result. My canister filter will kick over though and always turn on in my main tank so even if the HOB doesn't and I'm not home, the canister will pick up the slack. However, with 3 tanks, canister filters may not be the most cost effective option.