Blue Thumb PB1236 Elite Medium Cascading Waterfall Kit – Pondless Backyard DIY Water Feature System with Spillway

The Blue Thumb PB1236 Elite Medium 22" Cascading Falls Kit is a complete pondless waterfall system that creates a stream approximately 15 feet long and 2-4 feet wide. The ClearWater 4200 GPH pump recirculates water from three Large Basin Matrix underground reservoir boxes up to the 22" Elite Cascade Falls Box, where it spreads across a 22" spillway and flows down through a custom rock stream bed before disappearing back into the hidden basin below. No visible pond — just the sight and sound of a natural waterfall. Made in the USA by Blue Thumb, a family-run Midwest manufacturer. 22" Elite Cascade Falls Box — 5,500 GPH Max — Lifetime Warranty Elite Pump Canyon — Lifetime Warranty ClearWater 4200 GPH Pump — 18-Mo Warranty Basin Matrix 3 Large — 7.4 Gal/Cu.Ft. PondGard 10'x10' + 10'x20' — Both Liner Pieces Included PB1236 | Blue Thumb Elite | ~15-ft Stream | Made in USA What's Included Waterfall System 22" Elite Cascade Falls Box (#PB1113) — 22" spillway; 5,500 GPH max; 20"x33"x14.25"; Matala mat; landscape lid; detachable weir; Lifetime Warranty Elite Pump Canyon — one-piece octagonal molded vault; side-slot water entry; auto-fill spinweld (PB1342 autofill optional); Lifetime Warranty Pump Discharge Assembly with check valve 8 oz Pond Cleaner & Muck Buster Pump and Plumbing ClearWater 4200 GPH Pump (#PB1052) — 4,200 GPH max | 30 ft max head | 120V | 330-630W | 6.2A | 16' cord | 1.25" FPT outlet | water-cooled / no oil | direct drive | 18-Month Limited Warranty Black PVC Flex Pipe — 2"x25' Installation Kit — black foam sealant + PVC glue + hardware Liner and Basin PondGard Rubber Liner — 10'x10' (basin area) — 45-mil EPDM; 20-yr warranty PondGard Rubber Liner — 10'x20' (stream bed) — both pieces included Protective Underliner (non-woven geotextile) Basin Matrix — 3 Large — Blue Thumb modular underground reservoir; 7.4 gal/cu ft (3x more than gravel) Not Included Rocks and gravel (required for waterfall stack + stream bed + basin cover) LED lighting (optional — Blue Thumb light kit sold separately) Auto-fill kit PB1342 (optional — attaches to Pump Canyon spinweld) Extra PVC pipe for stream runs beyond 25' Rocks and gravel are NOT included and must be sourced separately. A 15-ft stream typically requires 3-5 tons of decorative boulders, river rock, and pea gravel — budget and plan for this before ordering. Technical Specifications Specification Detail SKU / Model PB1236 | Blue Thumb Elite Medium 22" Cascading Falls Kit Stream Size ~15 feet long x 2'-4' wide (maximum; varies by design and grade) Cascade Falls Box 22" Elite Cascade Falls Box (#PB1113) — 5,500 GPH max | 22" spillway | 20"x33"x14.25" | Matala mat | Lifetime Warranty Pump Canyon Elite Pump Canyon — octagonal one-piece molded | auto-fill spinweld | Lifetime Warranty Pump ClearWater 4200 GPH (#PB1052) — 4,200 GPH | 30 ft max head | 120V | 330-630W | 6.2A | 16' cord | 18-Month Warranty Liner (basin) PondGard 45-mil EPDM — 10'x10' — 20-year warranty Liner (stream) PondGard 45-mil EPDM — 10'x20' — 20-year warranty — both pieces included Underliner Protective non-woven underliner (included) Basin Basin Matrix — 3 Large — 7.4 gal/cu ft (3x more than gravel) Pipe Black PVC Flex Pipe — 2"x25' Treatment 8 oz Pond Cleaner & Muck Buster Origin Made in the USA — Blue Thumb, family-run Midwest manufacturer Note on the Cascade Falls Box: The 22" Elite Cascade Falls Box is a spillway/distribution box — not a biological waterfall filter. It distributes water evenly over the 22" weir using an internal Matala mat, but contains no bio-media. Cascading falls systems don't require biological filtration because there are no fish in the basin. This is different from the Elite Biological Waterfall Filter used in Blue Thumb's Elite Pond Kits (PB1250, PB1267, etc.). If you want a fish pond rather than a pondless waterfall, see the Elite Pond Kit series. How It Works The ClearWater 4200 pump sits inside the Elite Pump Canyon at the lowest point of the installation. Three Large Basin Matrix boxes surround the Canyon and create the underground water reservoir. When the pump runs, it lifts water through the 2"x25' PVC flex pipe up to the 22" Elite Cascade Falls Box at the top of the waterfall. Water passes through the Matala mat inside the box, spreads evenly across the 22" spillway, then flows down the rock waterfall and stream you build, disappearing back into the rock-covered Basin Matrix to begin the cycle again. The two liner pieces — 10'x10' in the basin and 10'x20' along the stream bed — create the watertight envelope that keeps every drop in the system. Elite Cascading Falls Series Kit Spillway Max Stream Pump Basin PB1229 Small 14" ~5 ft 2,340 GPH 2 Small Basin Matrix PB1236 Medium 22" ~15 ft 4,200 GPH 3 Large Basin Matrix PB28KIT 28" 28" ~15 ft 6,000 GPH 3 Large Basin Matrix PBE30CFK Large 30" ~17 ft 6,000 GPH 3 Large + 3 Small PBE40CFK XL 40" ~18 ft Illumiflow 6000 3 Large + 3 Small Frequently Asked Questions What is included in the Blue Thumb PB1236 Elite Medium Cascading Falls Kit? Complete component list: 22" Elite Cascade Falls Box (#PB1113) (5,500 GPH max, lifetime warranty); Elite Pump Canyon (lifetime warranty, auto-fill spinweld); ClearWater 4200 GPH Pump (#PB1052) (4,200 GPH, 16' cord, 18-month warranty); Basin Matrix — 3 Large (7.4 gal/cu ft underground reservoir); PondGard 45-mil Rubber Liner — 10'x10' AND 10'x20' (two separate pieces, both included); Protective Underliner; Pump Discharge Assembly with check valve; Black PVC Flex Pipe 2"x25'; Installation Kit (black foam sealant, PVC glue, hardware); 8 oz Pond Cleaner & Muck Buster. Creates approximately 15-ft stream, 2-4 ft wide. Rocks and gravel not included. What are the benefits of the Elite Pump Canyon and Cascade Falls Box? Both structural components carry Lifetime Warranties. The Elite Pump Canyon's octagonal design resists ground pressure distortion; the auto-fill spinweld accommodates the optional PB1342 autofill kit. The 22" Elite Cascade Falls Box distributes pump flow evenly across the full 22" spillway using an internal Matala mat — creating a smooth, uniform waterfall curtain. Note: the Cascade Falls Box is a spillway box only; it does not provide biological filtration (not needed in a pondless system). The included ClearWater 4200 pump carries an 18-Month Limited Warranty separately from the lifetime structural warranties. What pump comes with this kit, and how does it work? The PB1236 includes the Blue Thumb ClearWater 4200 GPH Pump (#PB1052) — a direct-drive submersible pond pump rated at 4,200 GPH maximum flow and 30 feet maximum head height. It runs on 120V, draws 6.2 amps (330-630W depending on head height), has a 16' power cord, and a 1.25" FPT outlet. It is water-cooled and oil-free. The pump operates via simple on/off switch — there is no wireless control, no smartphone app, and no variable-speed feature. The included Pump Discharge Assembly allows basic flow direction, and an inline valve can be added if more precise throttling is needed. The 22" Elite Cascade Falls Box handles up to 5,500 GPH — the 4,200 GPH pump is correctly sized with headroom for taller waterfall installations. Why use Basin Matrix instead of gravel? Blue Thumb's Basin Matrix modular boxes store 7.4 gallons of water per cubic foot, compared to approximately 2.2 gallons per cubic foot for gravel. Three Large Basin Matrix boxes hold over 3x more water in the same excavation footprint as a gravel basin. This means smaller, shallower excavation, less heavy material to haul, a larger water buffer for continuous pump operation, and an open-frame structure that keeps the pump accessible for servicing. The boxes stack and interlock over the liner to create a structural grid that supports rock and decorative stone above without collapsing. Is the 45-mil EPDM liner safe for large rock installations? Yes. The PondGard 45-mil EPDM rubber liner is highly flexible, puncture-resistant, and rated for 20 years of outdoor use. It remains elastic at temperatures as low as -40 degrees F and resists UV, ozone, and oxidation. The kit includes two liner pieces: a 10'x10' piece for the basin and a 10'x20' piece for the stream bed. The non-woven protective underliner goes down first in both areas to cushion the rubber liner from sharp soil objects. Both liner pieces are foam-sealed where they meet the Cascade Falls Box using the included black foam sealant, creating a waterproof connection. Once sealed and covered with rock, the liner easily supports large boulders directly on top. How do I winterize the PB1236 in freezing climates? Pump: Remove from the Pump Canyon; rinse clean; drain completely; store indoors. The ClearWater 4200 is a direct-drive pump — do not leave it submerged in water that may freeze. Basin: Without the pump running, the basin drains naturally. Use a wet/dry vacuum to remove residual standing water from the Pump Canyon. Drain the liner fully to prevent ice expansion against liner seams. Stream bed: Ensure no low points trap standing water. The PondGard liner handles freeze-thaw well but pooled water that freezes can stress liner seams at low spots. Cascade Falls Box: Drain completely; remove the Matala mat if possible; the Lifetime-warranted box is frost-resistant but draining prevents internal freeze pressure. Also Available in the Elite Cascading Falls Series PB1229 Small (14" spillway) — ~5-ft stream; 2,340 GPH; 2 Small Basin Matrix PB28KIT (28" spillway) — same ~15-ft stream as PB1236 but wider, more dramatic waterfall PBE30CFK Large (30" spillway) — ~17-ft stream; 6,000 GPH Illumiflow pump PBE40CFK Extra Large (40" spillway) — ~18-ft stream; maximum waterfall width Blue Thumb PB1236 Elite Medium 22" Cascading Falls Kit: ~15-ft stream (2-4' wide). 22" Elite Cascade Falls Box (5,500 GPH max, lifetime warranty), Elite Pump Canyon (lifetime warranty), ClearWater 4200 GPH pump (18-mo warranty), Basin Matrix 3 Large, PondGard liner 10'x10' + 10'x20', protective underliner, Pump Discharge Assembly + check valve, Black PVC Flex Pipe 2"x25', installation kit, Pond Cleaner & Muck Buster. Made in USA. Rocks and gravel not included. Comparing kit sizes or need help planning your stream? Call or text (765) 508-4352 — Monday through Friday, 9 AM to 5 PM EST.