SunBlaster T5HO 6400K Replacement Lamp, 18"

Restore Full-Spectrum Output to an 18-Inch T5HO Fixture, 6400K

A T5HO fixture's ballast and reflector can outlast several lamps, and once output starts to fade after roughly 10,000 hours of use, a fresh 6400K lamp restores full-spectrum brightness without replacing the whole fixture. This SunBlaster replacement lamp is built to drop into a compatible T5HO fixture in place of a worn-out original.

At 18 inches, this lamp fits SunBlaster's 18-inch T5HO combo fixtures and other compatible 18-inch T5HO housings used on single shelves or small propagation setups.

Key Features & Benefits

• 6400K Spectrum — cool-leaning, blue-white output suited to vegetative growth and propagation stages.
• Drop-In Fixture Fit — sized to replace a worn T5HO lamp without modifying the fixture.
• Restores Full-Spectrum Output — reverses the gradual dimming that happens as a fluorescent lamp ages.
• ~10,000-Hour Recommended Interval — a practical checkpoint for scheduling lamp swaps before output drops noticeably.

Who Should Use This Replacement Lamp

This lamp fits any grower running a compatible T5HO fixture whose original lamp has dimmed, flickered, or reached the end of its practical service life. Swapping the lamp on a schedule instead of waiting for total failure keeps light output consistent from one grow cycle to the next.

About SunBlaster

SunBlaster designs and sells T5HO and CFL fluorescent lighting, LED strip lights, and related propagation hardware out of Langley, British Columbia. Selling replacement lamps separately from the fixture lets growers refresh output on their existing combo units instead of buying an entirely new fixture each time a lamp wears out.

Frequently Asked Questions

How do I know when to replace the lamp?

Most T5HO lamps show a noticeable drop in brightness by around 10,000 hours of use, even though they may not fully burn out for a while longer. If seedlings under an older lamp seem to stretch or grow more slowly than usual, a dimming lamp is a common cause worth ruling out first.

Will this lamp fit any T5HO fixture?

This lamp is sized to match SunBlaster's own T5HO combo fixtures at the same length, and most standard T5HO sockets use a common pin fitting. Always confirm the fixture length before ordering, since a lamp built for an 18-inch fixture will not fit a 12-inch housing or vice versa.

Why is the 6400K spectrum used for this lamp instead of a warmer color?

6400K sits toward the cooler, bluer end of the visible spectrum, which growers commonly favor for vegetative growth and propagation because it tends to encourage compact, sturdy growth rather than stretching. Warmer, redder spectrums are more commonly reserved for the flowering stage instead.

Can I mix this lamp with an older lamp in a multi-lamp fixture?

It's better to replace lamps in a fixture together rather than mixing a fresh lamp with a significantly dimmer one, since the difference in output can create uneven light across the canopy. If only one lamp in a two-lamp fixture has failed, replacing both keeps output balanced.

Is this lamp compatible with older SunBlaster fixtures?

Yes, as long as the fixture takes a standard T5HO lamp at the matching length and the ballast is rated for T5HO output. This replacement lamp does not include a ballast of its own, so it relies on the fixture's existing ballast to operate correctly.