Bio Filters

[Mylu]

Concerned with this quote from one of your articals.

"Please do not confuse old-fashioned hang-on filters with the smaller modern power filters in use today. Modern power filters with their small cartridges, foam pads, and spinning or whirling gimmick devices, will never be adequate for proper biological filtration, in spite of the misleading and exaggerated claims made by some manufacturers. "

I don't want to use any manufacture name.. ML....My oldest tank is very clean but I think it was the good bacteria not the "and spinning or whirling gimmick devices".

My new tanks have had trouble getting started. I seeded my last new tank with gravel from my oldest clean tank and it seems to be doing better. Jury not in yet.

My question is... Should I just get rid of the "spinning or whirling gimmick devices"?

[RichT]

My hang-on filters (Emperor 400) use 2 bio-wheels and I've never had a problem with them...at all. I've been using these type of filters for about9-10 years, now. The only time I had changed the bio-wheels was when I switched to SW. In fact, I had the same bio-wheels on my 55gal FW predator tank for nearly 8 years and never done a thing to them. I was always told that the slower they turned, the better they worked.

This is one thing I would not put in the same catagory as, in the words of my Grandpa, "Tom Foolery Stuff."

[AquariumPro]

Hi to both Mylu and RichT and welcome to the A Pro boards!

Mylu: The intention of that article was not to condemn modern compact power filters, but rather to condemn the way they are marketed, particularly to new hobbyists through the so-called "super-pet" stores and places like WalMart. Advertising that a small cartridge can provide enough suface area for proper biological filtration defies logic, but unfortunately, many new hobbyists fall for this because they don't know any better.

We have tested these filters and have found that more bacteria seem to grow on the internal plastic surfaces of the filter than the foam or cloth cartridges that are used in the filter. In a six month experiment, after operating six different models for four months in tanks of the same size and under roughly the same bio-load conditions, we removed the so-called "biolgical" components of the filters, and got no ammonia spikes, even after three weeks. But when we replaced the biological components, let the filters run for a month, then thorougly cleaned the filters without cleaning the biological media, we got high ammonia spikes in ALL six tanks, and four of them got very cloudy! Granted, these were not classic double-blind experiments with controls, but the statistical evidence was still pretty convincing.

We do not object to the smaller power filters, and you should not get rid of yours. They work very well to do the job that they were originally designed to perform, before some manufacturers got the not-so-bright idea of trying to make them into all-in-one solutions. These filters were designed to be mechanical chemical (carbon) filters and they work very well for that purpose. All tanks need good biological, mechanical and chemical filtration to look their best and maintain a healthy environment.

Not too long ago, we used undergravel filters along with the small power filter to get good filtration in all three categories, and this is still a good way to go for smaller freshwater tanks. The other method is to simply use a larger filter such as the Emperor filters by Marineland, or for tanks 30 gallons or larger, a canister filter. The idea behind sound biological filtration is to offer enough surface area in a filter so that enough bacteria can cultivate to convert toxic ammonia and nitrites into much less-harmful nitrates, which are then removed by periodic partial water changes.

An undergravel filter, using all of the surface area of the gravel, works quite well for this, but only for freshwater where there is plenty of available oxygen for both fish and aerobic bacteria to share. They have the disadvantage of trapping dirt in the gravel, but you should be vacuuming gravel anyway when you do a water change, so I fail to see many drawbacks to this old-fashioned but tried-and-true method in freshwater tanks. They are also relatively inexpensive.

However, building any biological filter up with a good bacterial population always requires stocking a tank very slowly and allowing the bacteria population to grow to catch up to the increased fish load before adding more specimens. That is critical no matter which method of filter is used.

[AquariumPro]

Rich T:

If you read the article, the one exception we state in that article ARE the Emperor filters, and we agree with you. The Emperors not only have very large bio wheels, they also come with fillable cartridges that can hold more media, so they don't fall into the same category indeed. They come the closest of all modern designs to the old-fashioned hang-on "big box" power filters made in the 1960s.

It is a shame that these filters are not still in production as their simple design allowed a lot of diversity and the flow they produced from their air-cooled powerful 1/6HP motors was amazing. Compare the 900 to 1000 gallons per hour and the full one gallon capacity of the old Supreme Super King to most of today's power filters and even some canisters, and there is just no comparison. We have been asking Danner (Supreme) to bring these filters back for years. They still have the tooling and could build them again. The motor these filters used is still being used to drive the Dynamaster II air pump. All they need is some encouragement from hobbyists and they could probably be convinced to do a small test production run. These filters could also be easily adapted as small wet/drys or refugiums as well and are large enough to house small protein skimmers.