Choosing the Right Filter....Which is right for me?
|This is a big question
that we get presented with all the time. With so many filters on the
market; biological, mechanical, pressurized, upflow, bead...you must
be going crazy! I will explain the difference here:
I will start with Bio Filters like the Tetra Clear Choice Filters and the FishMate Biological Filters. These filters sit on the outside edge of the pond. They are noticeable but can be hidden with landscaping or placed under a deck. The water is pushed from a submersible pump up to the filters inlet and then the water spills out and down by gravity. These filters are usually called bio filters, mechanical filters or gravity fed filters. These filters are great for filtering the water and some of the filters even come with a UVC built right in or an option to add one. They usually filter the water with a foam pad or multiple pads of different types such as carbon impregnated filters and a course polyester pad. There are sometimes other media as well for the bacteria to attach to like plastic bio media balls, lava rock, Supra Media (a natural rock substrate) or the like.
Pressurized filters like the FishMate Pressurized Filters, OASE Pressurized Filters and Tetra Pressurized Filters (coming soon) are becoming our most popular filters as they can be buried about 2/3 of the way in the ground which makes concealing them easy. They also have multiple foam pads and a bio media like the bio filters above. And an optional UVC built in on some models. The best thing about these filters is that they can lift water up to a waterfall or stream. They do this because these are enclosed and sealed with clamps therefore when the water is pushed up from the submersible pump into the filters inlet, pressure is built up inside the filter and will push the water through tubing up to a your water feature. It is recommended that you refrain from lifting water more than 3-4ft of total head lift from the filter up the point of discharge. There is another great feature on some of these pressurized filters and that is a unique backwash feature. On the FishMate filters this is called Powerclenz and you would just turn the dial on the top of the filter to discharge the waste from within the filter. The OASE Filters have a plunger type backwash feature which you move up and down to remove the waste. On the Tetra Filters it is also a dial like the FishMate filters. The backwash feature explained more in detail allows you to hook up a 2nd discharge tube from the filter to your garden and reverse the flow by just turning a dial or raising a lever on the filter. This will take the waste from the filter and discharge it into the garden or other area.
Upflow filters are used on the more professional installations. These filters are large boxes that have been engineered to filter your pond very efficiently. They use a filter pad usually made from polyester as well as a bio media that you will usually need to add yourself into a usually included media bag. Here are just a few of the Upflow Filter Models: Savio Living Ponds, Atlantic Water Gardens and PuriFalls. These filters are also waterfall boxes. Meaning that when the water is pushed up through the media it flows over a waterfall lip or what is referred to as a weir. There are a few models of upflow filters that discharge the water through a 2" pipe rather than over the weir. You can use an Upflow Filter with a submersible or external pump. They are most commonly used in combination with a Skimmer to cut down on maintenance but the Skimmer is not required.
Bead filters are the high end in filtration used mostly with Koi ponds or when the pond builder wants a convenient yet excellent filtration device. Also, great for heavy fish loads. The most popular Bead filters would be the Aqua Ultima II Filters. Bead filters are shaped like a barrel and are filled with media beads. Media beads allow the beneficial bacteria to propagate in the filter. These are plastic media with tons of surface area. The Aqua Ultima II Filters are easily backwashed by the flip of a lever using an internal jet washing system. Bead filters can usually be buried for hiding. Since the filters are sealed they can withstand pressure up to 50PSI (Ultima II Filters) and can push the water up many feet of head lift. You would mostly use an External pump such as the Sequence Centrifugal Pumps with them although you can also use some of the high pressure submersible pumps like the CalPump Waterfall or the Torpedo Pumps. In your figuring you will want to take off 10ft of head lift for the resistance in the filter. This means that if you are choosing an Aqua Ultima II 2000 you would choose a pump such as the CalPump PW3000, the Sequence 3200SEQ20 or the Sequence 6000PRM17 If you look at the gallons per hour discharge at 10ft on these pumps you will see that the numbers falls at or below 2000 gph which is the rating the filter.