Waterwood Water & Wood New 2 in 1 Underwater Air Driven Oxygen Releases Aquarium Fish Tank Pond Biochemical Stone Sponge Corner Filter

Filter works great. The filter had a crack when I received it. Fixed the crack and it still works great.

First off, I'm an Angelfish and Discus Breeder/Wholesaler. Been at it over 30 years. In the last 5 years my municipal water company has went downhill with its chemistry. Our water has always had a slightly alkaline PH (7.2) but in these last few years the PH is very prone to crashing in my tanks because the calcium hardness has dropped. To compensate I've been using crushed coral/aragonite in media bags to raise the KH and keep my PH stable.I like the fact I can substitute the coral/aragonite for the rocks/ceramic bio media to have both a biological filter along with a KH/PH buffer to keep my tanks stable.I have 2 problems with this filter. 1) The plastic that this filter is made of is brittle, like others have stated. Out of the box I have 1 out of 8 that cracked too easily while prepping them for use. 2) As an expert on filtration I am acutely aware of the fact that bio filters can be over driven. Any bio filter will be most efficient when the water has enough "hang time" to stay in contact with the water/biological organisms so they can have a chance to consume and convert the wastes of the fish. For the volume of these corner filters and the flow they are capable of, too much air/water flow will lesson its ability to be biologically effective and more of an particulate/mechanical filter.Now as far as these filters tank capacity of filtration and not having an overstocking situation, I can tell you that they will do well from 20 to 30 gallons max given the correct air/water flow. If they were square and had more volume then I would say up-to 40 gallons max.

This filter does not work how it is described on the box/in pictures. The back of the box clearly shows the air tube going through both compartments. But it stops at the first one. The bottom filter material doesn't even have a hole in it to allow for the advertised functionality.The result? Instead of the water coming in from the top, travelling down both compartments of media, and then rising up the tube, it instead just comes down the first compartment and rises from there, completely bypassing the second compartment.There are holes in the bottom that account for some water passing through the bottom compartment, But the media isn't set up correctly for that to be useful.The most disappointing thing is if it had worked as advertised it would be perfect. You could do your mechanical filtration with floss and sponge at the top, and fill the bottom compartment with bio media. The filter pictured on the box is brilliant.As it is, its just a waste. It does pretty much the same job as the single stack version of this filter. And honestly, its just damn misleading. Its not a fault, they clearly manufactured it differently than advertised on purpose hoping that people wouldn't notice. They mislead their customers on purpose and I hate it.

No good i had wool filters for years but shops stopped selling them seen this on amazon and thought i would buy it as i like wool filters better than the plug in one in shops now its bad within a hour i had wool floating around the tank water i had cleaned the filter before use in case anyone thinks that's the problem i did try a less powerful pump did the same thing so that was not the problem i would say it is a poor wool filter i would not buy it did come on time that's all that was good

Nice some of the gravel is just plain small rocks so not very bacteria house style but will do the job.