I bought my first Aquaclear HOB (hang on back) power filter in 1986. I think it was a 610 model, but can't be 100% on that. It was a wonderful filter that lasted many years until it got damaged during transit in 2001. However, it was replaced with another newer model (Aquaclear 60 HOB) that had been going strong until 2016 when someone decided to drop it on the floor and break the case.
The early versions like my first one had 3 compartments that went from right to left. Each compartment was separated by a plastic screen with holes in to allow water to flow through. As the sponges clogged up the water would bypass the sponges and flow over the top of them. So they had to be kept clean or they didn't work as well.
The newer models have done away with the dividers and have a mesh cage everything sits in. The side of this plastic cage helps direct incoming water to the bottom of the filter where it then flows upwards through various filter materials, before overflowing back into the tank. The new model is a much better design and more effective in regards the filter media and water flow.
The only drawback to the new design is when the filter sponges start to clog up. When they get really dirty, the entire cage with filter materials starts to lift up a bit. If you see this then your filter needs a clean.
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Pros
Cons
Summing up, I think they are a very good filter that is easy to set up, use and maintain, and they have a lot of filtration media for their size. Both of mine lasted 15 years and only got replaced because they were damaged by people. I replaced an O-ring once on the first model and that is all I have replaced.
The early versions like my first one had 3 compartments that went from right to left. Each compartment was separated by a plastic screen with holes in to allow water to flow through. As the sponges clogged up the water would bypass the sponges and flow over the top of them. So they had to be kept clean or they didn't work as well.
The newer models have done away with the dividers and have a mesh cage everything sits in. The side of this plastic cage helps direct incoming water to the bottom of the filter where it then flows upwards through various filter materials, before overflowing back into the tank. The new model is a much better design and more effective in regards the filter media and water flow.
The only drawback to the new design is when the filter sponges start to clog up. When they get really dirty, the entire cage with filter materials starts to lift up a bit. If you see this then your filter needs a clean.
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Pros
- Easy to clean
- Has space for 3 types of filter media. The filter comes with a bag of ammonia absorbing granules, 1 sponge and a bag of carbon. I leave the carbon and ammonia absorbing granules in the box and just use 3 sponges.
- Reliable.
- Adjustable flow.
- The motor is sealed in a plastic resin to prevent moisture getting onto the electrical circuits.
- The motor is very quiet, although there is some noise from water running back into the tank. However, this is helpful in aerating the aquarium water and can be reduced by having the aquarium water level higher so there is less noise from the water flowing back into the tank. Coverglass also reduce the noise and evaporation. All HOB filters have this noise.
- Spare parts (not normally needed) and additional sponges or other filter media are readily available.
Cons
- Hangs on the back, front or side of the tank and this can make it less attractive in a living area.
- Coverglass will usually have to be modified or left open a small amount for the filter to fit due to it hanging on the back, side or front of the aquarium. This means there will be a bigger gap in the top of the tank that is open and fish will have more chance of jumping out through the gap. Some fish also swim up the water flowing into the tank and swim around in the filter.
- Hoods also have to be modified for HOB filters
- The filter motor (pump) has to be lower than the water level in the aquarium. If the aquarium water level is lower than the pump, then the filter will struggle to suck up water and fill the filter if there has been a power failure and the water has drained out of the filter and back into the tank. However, the motors are very good and my pumps always worked after the filter was filled back up after a power failure, and we had a lot of power failures.
- The O-ring between the motor and filter case can dry out over time and start leaking, and they can leak from the same area if the O-ring doesn't seat correctly when you reassemble the unit after cleaning. This is easily remedied by smearing a small amount of Vaseline on the O-ring so it doesn't stick or pinch when putting it back on the case.
Summing up, I think they are a very good filter that is easy to set up, use and maintain, and they have a lot of filtration media for their size. Both of mine lasted 15 years and only got replaced because they were damaged by people. I replaced an O-ring once on the first model and that is all I have replaced.