Review | FishMate Gravity Flow Filters and UV Combo

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FishMate UV +Bio FilterFishMate Filters and UVC Combinations are Amongst the Very Best Yet are Low Cost

Bio filters alone DO NOT prevent green water ... do not believe anybody who tells you this is the case. You need an UV to be certain of removing suspended algae problems and correct UV wattage linked to  your pond size and fish stock density is important.

This FishMate UV + pond biofilter shown above is small in size despite being capable of handling the biological load from a pond of up to 1,000 US gallons.... it is one of the very few types of pond filters (maybe the only type in the USA) to contain the world class highly effective and efficient pond filter biomedia called Alfagrog. This is what creates the huge bio degradation capacity of this pond filter


There is far too much hype created around pond filters when all that is required is a well designed container with appropriate biomedia inside it. After all in a natural lake or river system the bacteria just cling to stones, rocks, and tree stumps.

The filter container is there just to hold the biomedia so that water can be pumped through the medium on which the bacteria live and do their job of purifying water. See below for a discussion about biomedia.

When a FishMate Pond Filter is combined with an UV as a single unit the manufacturer guarantees crystal clear pond water. Apart from this such a "combo" system will make installation much easier for you. You'll also know the equipment has been matched from a size or capacity perspective.

There is a wide range of FishMate units to cover small to large ponds.


As an example the FishMate Compact UV + Bio Pond Filter for ponds up to 1,000 gallons volume unit contains an 8 Watts UV lamp for excellent suspended algae control. This unit would not be effective in a pond of say 2,000 gallons. You would need say 16 watts of UV power for this size of pond or the next combo size up.

TAKE NOTE ... no UV light can remove blanketweed or string algae by the way. UV is only effective when algae is suspended in the water causing green or murky brown water problems that prevent you from seeing your fish. The UV clarifies or clears the water and hence the name UVC (Ultra Violet Clarifier). Some companies refer to sterilizers rather than clarifiers.

These FishMate UV + Bio "combo" units do 2 jobs at the same time ..... the bio filter cleans the pond water (biologically converts toxic ammonia and nitrites to nitrates which act as fertilizers for pond plants) while the UV lamp clears the pond water ... fish ponds almost always tend to go cloudy and green if no UV. The reason is the nutrients in the pond cause excessive algae growth and this prevents you seeing your fish.

If the UV unit is correctly sized it works every time all the time in removing suspended algae. I call it the "Blue Light Miracle Worker".

The Best All Purpose Low Cost biomedia Around

Until very recently I was not aware that Alfagrog was used in any American pond filter and was very pleasantly surprised when is stumbled across the FishMate pond filters and especially when I saw the low price of FishMate pond filters. The reason I was not aware is that Alfagrog goes by another name in the USA (SUPRA) ... here's a picture of Alfagrog or Supra.

alfagrog or supra filter media

Alfagrog is a highly porous ceramic filter media specially created for bio filters in the fish farming industries. Depending upon the size of the Alfagrog particles the area for bacteria colonization can be up 100 times that for most types of plastic filter media ... whether they be tubes, balls, or other fancy shapes.

Understanding pond filter biomedia

All biomedia in fish pond filters of any type can be classified according to its specific surface area (SSA). The higher the SSA the more probable is it that the biomedia will be more effective in a fish pond filter. SSA refers to how much surface area per unit volume of a type of media is available for colonisation by bacteria inside the actual filter system.

For products like simple plastic tubes the SSA is about 1 sq metre per litre of biomedia. In other words if a fish pond filter is filled with plastic tubes then for every litre used about 1 sq. metre of surface is provided for colonisation by the bacteria. Alfagrog will provide between 40 and 100 times more area than this in the SAME volume space.

How To Select Pond & Waterfall Pump  ... Make sure your pond's pump runs 24/7 to keep your pond filter working

How To Choose Fish Pond FiltersFor year round crystal clear water in ANY fish pond you need the right pump, a working bio filter and an ultra violet clarifier (UV). Click the green button to find out why you need a bio filter and UV light in water gardens and ponds...

USA ... water garden products at best prices on-line. Totally reliable and secure.

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