Atlantic Big Bahama FilterFalls Waterfall Filter – Large BioFalls for Koi & Ecosystem Ponds with High-Capacity Media

The Atlantic BF2600 Big Bahama FilterFalls is a professional-grade biomechanical waterfall filter rated for ponds up to 4,000 gallons with a 26” waterfall spillway and a pump flow range of 4,000–6,000 GPH. Water from your pond pump enters through the 2” FIPT bulkhead at the top of the unit and flows down by gravity through the biological media chamber before cascading over the overhanging spillway weir. The overhanging weir with drip edge prevents water from tracking down the face of the unit, eliminating the silicone seal failures common to DIY waterfall boxes. The expandable media chamber accepts up to six Matala filter mats and a variety of bio-media, allowing filtration capacity to increase as ponds age and fish loads grow. Multiple bulkhead locations on all sides of the bottom chamber give maximum plumbing flexibility. The reinforced high-molecular-weight polyethylene housing is warranted for life. Matched to the Atlantic PS7000 skimmer. Dimensions: 34.5”W × 25”D × 23”H. Filter media sold separately. $120 oversized shipping surcharge applies. BF2600 | 26" Spillway | 4,000–6,000 GPH | Up to 4,000 Gal 34.5"×25"×23"H | 2" FIPT | Matched to PS7000 Expandable Media Chamber | Overhanging Weir + Drip Edge Top-Feed Gravity Biomechanical | Lifetime Enclosure Warranty Why Choose the Atlantic BF2600 Big Bahama FilterFalls? 26” waterfall spillway for large ponds: The BF2600 delivers a full-curtain 26” wide waterfall at 4,000–6,000 GPH flow rates — wide enough to serve as the head of a serious koi pond stream, properly matched to the PS7000 skimmer for complete system balance. Up to 4,000-gallon pond capacity: The BF2600 is Atlantic’s mid-large FilterFalls, positioned between the BF1900 (2,000 gal) and BF3800 (8,000 gal). At 4,000 gallons, it handles the most common size range for large residential koi ponds — including heavily stocked ponds where biological load is highest. Expandable media chamber: The oversized interior accepts up to six Matala filter mats plus bio-balls, bio-rocks, or lava rock — all sold separately and added progressively as the fish load and pond age demand. A newly installed pond can start with a single mat and scale up without replacing the filter housing. Overhanging weir with drip edge: Most DIY waterfall boxes rely on silicone seals between the spillway face and a cap stone to prevent water from tracking behind the fall. Atlantic’s overhanging weir with integrated drip edge breaks the water’s surface tension at the lip, routing every drop over the front face — no silicone required, no seal to fail. Multiple bulkhead locations: The bottom chamber accepts 2” FIPT bulkheads on all four sides. This allows the plumber to route the incoming pipe from any direction — straight back, left side, or right side — without cutting or repositioning the unit after installation. One-piece liner flange with solid lip and molded inserts: The liner attachment system uses a one-piece compression flange — no drilling, no bolt patterns to align. The solid lip and molded inserts create a watertight liner bond that resists the ground movement and freeze-thaw cycling that causes traditional flange systems to leak over time. Biomechanical three-stage filtration: The BF2600 provides three distinct filtering actions in sequence: (1) the mesh media bag pre-filters coarse particles; (2) the filter mat(s) provide mechanical and biological filtration simultaneously; (3) bio-media (sold separately) adds colonization surface area for nitrifying bacteria. Open swirl chambers maximize water contact time with media at each stage. Annual maintenance cycle: Because biological filters rely on bacterial colonies rather than disposable filter cartridges, the BF2600 typically requires only annual cleaning — a full rinse-down at spring startup. Mid-season cleaning is rarely needed in properly sized systems. Lifetime warranty on enclosure: Atlantic warrants the BF2600 FilterFalls housing for life. The warranty covers the polyethylene shell against structural failure — media and hardware items are consumable and not included in the lifetime coverage. Technical Specifications Specification Detail Model BF2600 Atlantic Item No. 73936 PPD SKU 00217 Waterfall Spillway Width 26 inches Pump Flow Range 4,000–6,000 GPH Max Pond Volume Up to 4,000 gallons Dimensions 34.5”W × 25”D × 23”H Bulkhead 2” FIPT (multiple locations on bottom chamber) Liner Attachment One-piece liner flange, solid lip, molded inserts — no drilling required Filtration Type Top-feed gravity biomechanical (3-stage) Media Chamber Expandable — up to 6 Matala filter mats + bio-media (sold separately) Spillway Design Overhanging weir with drip edge Construction High-molecular-weight polyethylene Matched Skimmer Atlantic PS7000 Filter Media SOLD SEPARATELY (Matala mats, bio-balls, bio-rocks, lava rock) Shipping Oversized Warranty Lifetime (enclosure) Not for use in Swimming pools or salt water What’s Included Atlantic BF2600 FilterFalls unit Installation kit Male thread adapter One-piece liner flange Media bag(s) for bio-tech media Bio-tech filter mat(s) Removable bottom grate and top grate Filter media is not included and must be ordered separately. Atlantic Matala filter kits (custom cut for BF2600), bio-balls, bio-rocks, and lava rock are all available as separate additions. Budget for filter media in addition to the unit cost. BF2600 in the Atlantic FilterFalls Family All Big Bahama FilterFalls share: high-molecular-weight polyethylene construction, overhanging weir with drip edge, one-piece liner flange, expandable media chamber, multiple bulkhead locations, and Lifetime enclosure warranty. Model Spillway Flow Range Max Pond Dimensions (W×D×H) Bulkhead Matched Skimmer BF1600 16" 1,000–3,900 GPH 1,250 gal 21.5"×19.5"×17.75" 1.5" FIPT PS3900 BF1900 19" 2,500–4,000 GPH 2,000 gal 28"×25"×21.5" 2" FIPT PS4600 BF2600 (this) 26" 4,000–6,000 GPH 4,000 gal 34.5"×25"×23" 2" FIPT PS7000 BF3800 38" 6,000–8,000 GPH 8,000 gal 46.5"×30"×23" 3" FIPT PS15000 Frequently Asked Questions How does the Atlantic BF2600 FilterFalls provide biological filtration? The BF2600 is a top-feed gravity-flow biomechanical filter. Your pond pump pushes water from the pond through a pipe to the 2” FIPT inlet at the top of the unit. From there, water flows downward by gravity through the filter media sequence inside the chamber before cascading over the 26” spillway weir into the stream or pond. Three-stage filtration occurs in sequence: the media bag pre-screens coarse particles; the filter mat(s) provide simultaneous mechanical and biological filtration; and optional bio-media (bio-balls, bio-rocks, or lava rock, all sold separately) add colonization surface area for nitrifying bacteria. Atlantic’s custom-cut Matala filter kits provide 62 sq. ft. of bacterial surface area per square foot of black mat — up to 124 sq. ft. per square foot for the blue-grade mat. The result is water that enters the FilterFalls carrying suspended solids, ammonia, and nitrites, and exits clean, aerated, and biologically processed before returning to the pond as a waterfall. What pump flow rate do I need for the BF2600? The BF2600 requires a pump delivering 4,000–6,000 GPH to the FilterFalls inlet. Running below 4,000 GPH will produce a thin, streaky waterfall across the 26” spillway rather than the full curtain the unit is designed for. Exceeding 6,000 GPH can overwhelm the biological media bed, reducing contact time and filtration efficiency. For pump sizing: account for head pressure loss from the elevation rise between the pond surface and the FilterFalls inlet. A pump rated at 6,000 GPH at zero head will deliver significantly less flow at 4–6 feet of elevation. Match your pump’s performance curve to the BF2600’s 4,000–6,000 GPH range at your installation head. Atlantic’s PS7000 skimmer is specifically matched to the BF2600 and includes a compatible pump chamber for this flow range. For reference, the full FilterFalls family flow ranges: BF1600 (1,000–3,900 GPH) | BF1900 (2,500–4,000 GPH) | BF2600 (4,000–6,000 GPH) | BF3800 (6,000–8,000 GPH). Is the BF2600 FilterFalls durable enough to be buried and loaded with rock? Yes. The BF2600 housing is molded from high-molecular-weight polyethylene — a dense, impact-resistant thermoplastic specifically selected for its resistance to soil pressure, freeze-thaw cycling, and UV exposure. The reinforced body with structural ribbing prevents wall bowing or deformation under sustained backfill and stone loads. The heavy-duty removable top grate and internal support bars are engineered to carry the weight of natural fieldstone and gravel camouflage — a load that hollow-core spillway covers cannot sustain. Atlantic designs for installations where the unit is completely buried and concealed by rock, with only the spillway weir visible at the stream edge. How does the one-piece liner flange attach to my pond liner? The BF2600 includes a one-piece liner flange designed for tool-free, leak-free liner attachment. The solid lip and molded inserts clamp the liner material between the flange faces, creating a compression seal that does not require drilling, bolt patterns, or silicone in the primary sealing surface. The flange is compatible with 45-mil EPDM pond liner. The overhanging weir with drip edge above the liner attachment point provides a secondary line of defense: water breaking over the spillway face drips clear of the flange attachment area, preventing the moisture intrusion that causes liner compression seals to degrade in conventional waterfall boxes. How often does the BF2600 filter media need to be cleaned? In a properly sized system, the BF2600 typically requires only annual cleaning — a full rinse-down at spring startup after winter dormancy. Mid-season cleaning is rarely needed because biological filters operate through living bacterial colonies rather than disposable cartridges. The bacteria in the media continuously process ammonia and nitrites as long as the filter runs. Important: always rinse the filter mats and bio-media with pond water, never with chlorinated tap water. Chlorine kills the bacterial colonies, which can take 4–6 weeks to re-establish. A simple bucket of pond water on the day of cleaning is sufficient. In heavily stocked koi ponds or during summer peaks in fish load, a mid-season rinse may be warranted. Atlantic’s expandable chamber allows you to add additional Matala mats or bio-media if you notice reduced clarity between annual cleanings. What filter media do I need, and is it included? Filter media is not included with the BF2600 and must be ordered separately. The unit ships with media bag(s) and filter mat(s) to get you started, but the biological media that colonizes the beneficial bacteria colony is a separate purchase. Atlantic offers several media options compatible with the BF2600: Matala filter kits (custom cut for BF2600): Available in black (62 sq. ft./sq. ft. surface area), green (96 sq. ft./sq. ft.), and blue (124 sq. ft./sq. ft.). Higher surface area = more bacteria = better filtration for heavily stocked ponds. Bio-balls: Plastic media providing high surface area in a loose-fill format. Good for the bottom chamber and media bags. Bio-rocks / lava rock: Natural porous media with high surface area at low cost. Typically used as a starting media layer for new ponds. For a newly installed pond, a single layer of filter mat and one bag of bio-media provides adequate filtration. As the pond ages and fish load grows, additional Matala mats can be stacked in the expandable chamber — up to six mats total — without replacing the filter housing. Why Buy Atlantic Products from Pond Pro Direct? Authentic Atlantic/OASE products with Lifetime enclosure warranty and full US support Pond design expertise — call for help sizing your pump, matching your skimmer, and selecting the right FilterFalls for your pond volume Price Match on identical Atlantic products from authorized retailers Atlantic BF2600 Big Bahama FilterFalls — 26” spillway | 4,000–6,000 GPH | up to 4,000 gal | 34.5”×25”×23”H | 2” FIPT | top-feed gravity biomechanical | expandable media chamber | overhanging weir + drip edge | one-piece liner flange | matched to PS7000 | Lifetime enclosure warranty. Filter media sold separately. Not for pools or salt water. Questions about pond volume, pump matching, or system design? Call or text (765) 508-4352 — Monday through Friday, 9 AM to 5 PM EST.