Although this model may be good in terms of dependability and cleaning efficiency, it is not quiet nor is it user-friendly in terms of maintenance. The old Whisper it was supposed to replace is better on both fronts. The pump on the AquaClear 70 could be quieter, and the water falls almost a couple of inches in the air before hitting the water-- and yes, the tank is full to half-inch from the top. I guess it was designed this way to promote aeration of the water, but it is noisy.

This filter is great, but the biological part of this filter needs to be replaced (i believe 2-3 months), I don't know if the biomax will lose performance if you dont. Other than that it is a great mechanical filter. When compared to penguin's filters this filter wins in mechanical filtration, but the penguin in biological. They also make the same amount of noise, but this one makes alittle more because it requires a higher water level than the penguin filters. However, one thing in this filter that the penguin doesn't have is the flow control which is really nice b/c sometimes i will move filters around to smaller to bigger tanks. Oh and this option let's you reduce more impurities out of your water (if you want to). Other than that it still has the same restarting problems as the penguin filters.

I purchased 2 new ones for my 65 gallon tank, and their function has been flawless in over 1 year. They seem to pump a lot more water than any comparably sized or priced filters. They are easy to disassemble, maintain & clean. The easy to understand manual and parts diagrams are available on line at the [...] web site. I recently purchased a third unit at a garage sale which had been dumped in a storage box and unused for a long time. I tested it and it worked fine the first try..! All it needed was a replacement O ring for the motor. Parts are easily identified and available. Hagen Aquaclear will certainly be the power filters I will use for my next aquarium.

These filters have kept my tanks vvery clean. Mine are quiet, pump a lot of water, but as a hint, I over filter every tank I have by at least 4 times. For now the filters and carbon are also free shipping

I worked in a pet store for 5 years and this is the best on the back filter you can get the spongs can be rinced for a long time and the amo carbin can be rechared in salt water over night in a small bowl use no iadine table salt.