Strange noise from t5s when turned off

[Reef-roach]

I posted this on the t5 thread yesterday but haven't heard anything back yet. Hoping someone can help.

Just setup a reef in August. Always done halides with great results in the past but my current setup has a tight short canopy. Seen mixed results with the limited number of led setups I've seen in person. Decided on t5s and lurked the forums for months researching before purchasing. Decided on miro let 8x80 retro to fit inside my canopy as I've heard the reflectors are a close second to Ati. I've been totally happy with it. Last week, however, I noticed a sporadic loud metallic click one to six times every night within five minutes of the lights turning off. Sounds like if you spin the reflector around the bulb. It seems unlikely it's been happening every night for five months without noticing until now. The ballasts are remote so I have ruled them out. I can't pinpoint the source of the sound but it seems as though it's coming from the bulbs or the reflector. Anyone have insight or trouble shooting suggestions? Is it possible the bulbs cool and contract when shut off and creates the reflector noise? Any ideas are appreciated!

 

[ReeferBob]

I would guess it is the reflector cooling.

 

[Reefing Madness]

I would guess it is the reflector cooling.

I agree. Suprised you didn't hear that same thing with the Halides.

 

[Reef-roach]

Thanks for the reply, ReeferBob. Have you experienced similar? Like I stated above, I hadn't noticed it before last week.

 

[Reef-roach]

Well thank you, gentlemen. I started to panic a little.

 

[Reef-roach]

I agree. Suprised you didn't hear that same thing with the Halides.

So am I, I ran 250s for about 4 years but they weren't enclosed in a canopy and didn't have parabolics. Maybe the flatter reflectors didn't trap the heat?

 

[Reefing Madness]

Ah, the unit probably kept the sound down. I use a Bat Wing Reflector and hear it all the time when the lights go out.