The preferred filter for any tank should be based more on the size of the tank and what is in it than anything else. There are a few filters that are well known for issues, such as the Magnum canister filters... (they break down often, clog easily, and parts for them can be hard to come by and expensive)
Aquaclear makes a pretty good series of filters. I have Aquaclears that have been running on various tanks for over 15 yrs now and are still going strong. Whisper, Aqueon, Marineland (Penguin), Rena, PennPlax, Eheim... all great brands of filters, each with their good points.
The animals being kept in the tank make all the difference. If you have fish that require a slow moving current, such as a betta, then Aquaclear would not be my first pick due to the heavy output of water they put into the tank, which creates a rather fast moving current. For that kind of situation, a canister filter or internal filter would be better options. For fish such as Goldfish
, comets or fancy, where the waste output is very high... an extra filter is always a good thing, but working with something that has a good turnover rate, such as the Aquaclear, would be a good option.
Aeration is another consideration. Do you need more aeration in the tank for fish such as Goldfish
, who consume/use a lot more oxygen than most other fish species? In that situation, water that breaks the surface of the tank will help to add aeration (and to cool water temps, especially without a cover), so working with a canister filter can be a good option, but be sure to include a power head or 2 (depending on tank size) to help with proper and full circulation in the tank. A spray bar from a canister can be positioned above the water line to achieve this effect, or lowering the water level with a hang on filter in place can also accomplish this.
These are just a few examples of how delicate filter choices can be, and why someone else should never be selecting/suggesting a filter for your situation without all information about your tank. Its great to ask what people think of each filter make/model, so you can hear about potential problems any may cause you if you select it... but always remember that is only a small part of what needs to be considered.
Hope this helps.