Two observations before the question which is related to both observations.
1) Way back to Olson, R. J. in 1981 in his article ” Differential photo inhibition of marine nitrifying bacteria, Journal Marine Research” the effect of light on those essential bacteria has been known.
Yet the manufactures of aquarium filters continue to expose their filter media to light by translucent covers. In particular, bio-wheels which should be among the most effective filters seem to be the ones most exposed to light.
The 2nd related concern is that the volume of media does not seem to go up as rapidly as the flow rate on many of the filters. The difference of size of the media a up to 20 gallon power filter and that for say the 20 to 30 gallon filter just does not seem to add at least 30% more area.
What seems to change is the volume of water flowing through the media. I. would not mind paying more initially for media if I knew that it would last a long time and that it would serve the needs of my fish better.
Now to justify the forthcoming question, I am not attempting to find a maintenance free filter nor am I trying to cram all my fish into one tank. I am looking to get the maximum benefit for my pets.
What would be wrong with a filter that would consider those factors by shielding the media and essentially be about the full length of the hood with a pump that would meet the minimum of filtering the water 4 times an hour, but could be paired with a second pump if the fish you are maintaining come from an area of faster flowing streams?
Or do such filters already exist? If they do, could someone post a web site for them.
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