Omega 315W CMH Fixture — Full Spectrum Ceramic Metal Halide Lighting at Entry-Level Pricing
Best for: New and budget growers wanting efficient, full-spectrum lighting without the heat penalty of traditional HPS
Our thoughts
The 315W CMH is one of those rare pieces of kit where you genuinely get professional-grade spectrum at a sensible price. Omega's done well here — ballast and reflector built in, no messing about with adapters, and you're looking at serious PAR output on just 315 watts. One we recommend a lot for growers moving from basic setups into something that actually delivers results.
The Omega 315W CMH Fixture is a complete ceramic metal halide lighting system combining ballast and reflector into a single unit, designed for growers who want genuine full-spectrum output without paying premium prices or battling excessive heat. This is proper HID performance that sits somewhere between traditional HPS and LED — you get the spectral quality of both without the worst bits of either.
How it compares
Against other 315W CMH fixtures and traditional grow lights:
- Outperforms 400W metal halide or 600W HPS for spectrum quality and efficiency
- Delivers 615umol/S PAR at 1.9umol/W — significantly higher than standard HID
- Runs cooler than equivalent HPS, reducing cooling costs and complexity
- Full daylight spectrum (CRI 90+) works for veg and flower without compromise
- More affordable than Gavita or Sun System equivalents; UK stock, no waiting
Simple maths: a 315W CMH footprint is roughly equivalent to 700W of HPS in terms of coverage and quality, but at half the wattage and half the heat.
Usage guidance
This fixture works best in smaller controlled spaces where that full-spectrum, low-heat output actually shines:
Small tent setup (1m² and under)
This is the sweet spot. Use as your standalone light. Coverage is even across that footprint, intensity is solid, and you'll keep temperatures manageable without industrial cooling.
Supplemental lighting
Run it between two HPS fixtures or alongside LED panels. CMH fills gaps in the red spectrum that HPS can miss, and adds UV that most LEDs don't deliver.
Initial setup
Important: fire up the fixture for a minimum 15 minutes continuously when you first use it. The ceramic arc tube and internal salts need to properly fuse. Skip this and you risk lamp failure and warranty trouble.
Bulb choice matters
Comes without a lamp — you'll need a separate 315W CDM bulb. Choose 3000K for flowering, 4000K for veg, or the 3000K for full-cycle growing if you don't fancy swapping.
Technical specifications
- Power output: 315W
- PAR delivery: 615umol/S
- Efficiency rating: 1.9umol/W
- Light spectrum: Full daylight spectrum, CRI 90–92
- Available colour temperatures: 3000K (flower-friendly) or 4000K (veg-friendly)
- Lamp compatibility: 315W CDM/CMH (lamp not included)
- Reflector type: Euro-style hammertone reflector, adjustable
- Lamp holder: PGZ pre-installed (no adapter needed)
- Ballast: Integrated, built-in thermal protection
- Lamp lifespan: Up to 24,000 hours, maintains 80% intensity for 20,000 hours
- Warranty: 5-year manufacturer's warranty
- Heat output: Significantly lower than equivalent HPS
Who this is for
- First-time indoor growers setting up a small tent who want results without guesswork
- Growers moving up from fluorescent or basic LED setups wanting serious PAR
- Budget-conscious cultivators who refuse to compromise on spectrum quality
- Operators running spaces under 1m² where HPS overkill means wasted heat and energy
- Anyone currently using HPS who's tired of cooling bills and wants lower-heat alternative
Our take
This is a proper ceramic metal halide system at a price that actually makes sense. You're not paying for brand polish — you're getting proven HID technology that delivers full-spectrum light, serious PAR, and low heat without the premium tag. The ballast and reflector are already integrated, so no hunting for compatible parts or dealing with European kit that needs adapters.
Best suited to small tent growing or supplemental use where that efficiency and spectrum really matter. Worth picking up while clearance stock lasts — a 315W CMH is one of the smartest lighting decisions a new grower can make.
