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Matala EzClear — the value in-line UV clarifier with a Philips lamp and a quartz sleeve
EzClear plumbs in-line between pump and filter (or filter and pond). A Philips T5 germicidal lamp inside a high-transmission quartz sleeve kills free-floating algae; a transparent cover lets you see the blue glow and know it is working. Choose the multi-barb body (¾"–1½" hose) or the 2" union body for hard pipe.
- Lamp
- Philips T5, 16–75 W
- Ports
- Multi-barb ¾–1½" or 2" union
- Pond (Matala)
- 3,000–10,000 gal
- Koi pond (Matala)
- 1,600–5,000 gal
- Lamp life
- 9,000 h
Image coming soon
Mystic Koi’s take
Pick the 2"-union version if you are plumbing with rigid PVC — unions make the yearly lamp change painless. Size from the koi column, then check flow: an EzClear 40W passes 3,500 GPH, so on a 5,000 GPH pump you need the 75W or two units in parallel. The 16W is the native match for the BioSteps II.
What it does
- Philips T5 lampIndustry-standard germicidal lamp, 9,000 h rated life.
- Quartz sleeve>95% UV transmission; replaceable.
- Transparent coverSee the lamp glow at a glance.
- Two bodies4-step hose barb or 2" half-union (ABS + PVC).
- UV-resistant housingBuilt to sit in the sun.
- Full parts supportLamps, sleeves, ballasts and fitting bags stocked.
EzClear specifications (per Matala)
| Model | Lamp | Max flow | Pond up to | Koi pond up to | MK koi rec. (20 W/1,000 gal) | Ports |
|---|---|---|---|---|---|---|
| EUV-16W / EUV2-16W | 16 W | 1,600 GPH | 3,000 gal | 1,600 gal | 800 gal | 1½" barb / 2" union |
| EUV-25W / EUV2-25W | 25 W | 2,000 GPH | 4,000 gal | 2,500 gal | 1,250 gal | 1½" barb / 2" union |
| EUV-40W / EUV2-40W | 40 W | 3,500 GPH | 6,000 gal | 3,500 gal | 2,000 gal | 1½" barb / 2" union |
| EUV-75W / EUV2-75W | 75 W | 5,000 GPH | 10,000 gal | 5,000 gal | 3,750 gal | 1½" barb / 2" union |
Our rule for stocked koi ponds: about 20 W of UV-C per 1,000 gal and roughly one pond turnover per hour through the unit, never above the maker’s rating. Matala’s own pond figures are shown first.
Which size do I need?
Green bar = Matala’s koi-pond rating. Our own stocked-koi rule (20 W per 1,000 gal) is stricter still — see the table.
Pairs well with
The science: how UV-C clears green water (and what it can’t do)
Free-floating single-cell algae turn pond water green. UV-C light at 254 nm damages their DNA as they pass the lamp, so they clump and get trapped by the mechanical filter. Dose = intensity × contact time, which is why flow rate matters as much as wattage: push water past the lamp too fast and the dose drops. Koi ponds carry far more nutrients than water gardens, so Matala rates koi ponds at roughly half the gallons of a general pond. UV-C does not touch string algae on the walls or replace biological filtration.
- Matala Water Technology Co. (2026). EzClear, Immersion and Spectrum UV-C clarifier data sheets. matala.com.tw.
- Hijnen, W.A.M., Beerendonk, E.F., Medema, G.J. (2006). Inactivation credit of UV radiation for viruses, bacteria and protozoan (oo)cysts in water: a review. Water Research 40(1): 3–22.
- Signify/Philips (2024). TUV T5 germicidal lamp specifications — 9,000 h useful life.
Questions we get about the EzClear
Multi-barb or 2" union?
Barb for flexible hose (¾"–1½"); union for 2" rigid PVC. Same lamp and ratings.
Can I run it after the filter?
Yes — UV works best on filtered water (less debris shading the lamp). Pump → filter → UV → pond is ideal.
How often do I change the lamp?
Every spring. Output decays before the lamp dies.
Matala at Mystic Koi
Matala filter media and pond equipment have been a koi-keeping staple for decades, and Mystic Koi has sold and run Matala gear in our own systems since we opened in Upland, California in 1996. Everything on this page ships from Matala USA (Sea Life Designs) or our ¾-acre facility. Not sure what fits your pond? Call or visit and we’ll size it with you.