Canister Filter vs Hang-On-Back Filter
A hang-on-back filter is simple and affordable. A canister sits out of sight and holds more media, which suits larger planted layouts.
| Canister filter | Hang-on-back filter | |
|---|---|---|
| Media capacity | Large | Small to moderate |
| Looks | Only pipes in the tank | Visible box on the rim |
| CO2 loss | Low surface agitation | Waterfall outflow drives off CO2 |
| Noise | Quiet | Can trickle |
| Maintenance | Less often, more involved | Quick and easy |
| Cost | Higher | Lower |
Choose Canister filter if
- You run a tank of about 20 gallons or more
- You inject CO2
- You want a clean, minimal look
Choose Hang-on-back filter if
- You have a small or budget tank
- You want the simplest maintenance
- You do not inject CO2
The bottom line
Planted tanks with CO2 benefit most from a canister. For small, low-tech tanks a hang-on-back filter does the job at a fraction of the cost.