When to change light bulbs?

[BigTruck6o2]

I have 3 175W MH bulbs, and they are about a year old right now, if I remember correctly your supposed to change them once a year or so. Just trying to see if I am thinking the right thing or not. TIA

 

[IndyReefMan]

I change my MH once per year and my PC once every 6 months.

 

[melosu58]

I dont know about MH but I do know I`m supposed to change my VHO`s every 6 months

 

[seaham358]

VHO 6-8 months , MH once a year and PC if I remember right 10-12 months.

 

[melosu58]

You mean I could have squeezing out another two months out of my VHO`s.

 

[seaham358]

As long as my corals look good and I dont have any cyno growing I squeeze every hour I can out of those babies..

 

[MadManMac]

Be careful with the blanket numbers! A MH that runs 6 hours a day will last twice as long as one that runs 12. Look at the averages for a particular type of bulb and watch your tank. The tank will tell you when things have changed. Be ready and have the bulbs on hand when things start to look different, if you wait to order it may cost you some grief with unwanted growth. I learned the hard way.

 

[melosu58]

I dont want to wait for something to getn ready to happen. I change mine every 6 months (VHO) no matter what because I dont want algea or cyno or anything else to get a foot in the door. But that`s just me.

 

[BigTruck6o2]

maybe that answers some of my questions then...my corals have been acting kinda strange like not opening occasionaly, and im starting to get alot more cyno then i used to have...but then again my bulbs are about a year and 3 months old..ill change them and see if i notice a difference. It isnt my water so im saying its the lights. 8O

 

[melosu58]

It`s worth a try

 

[seaham358]

I would change them out ASAP, not sure what kind you have or how many but try and change them out gradually giving the tank a chance to adjust to the new lighting. If you have 5 bulbs change out 2 and a month later change out the other 2 . Something like that. As bulbs get old the color spectrum changes and this can bring on cyno... But you als need to check for phoshphates if you have cyno, it needs fuel.

 

[Brenden]

Exactly how does the spectrum change as the bulb gets older? People run everything from 20k bulbs to 6,500 bulbs without issues. How do older bulbs change that makes them cause "problems"

 

[melosu58]

That`s a good question but I`ve always been told that also about the spectrum changing. I think it`s got something to do with trhe gas inside of them. I think. We need a lighting expert here.

 

[seaham358]

Im no expert , its my understanding that the color that they produce changes to a red spectrum and this helps promote algae growth and is not right color for coral growth.. Maybe Steve S will help out here... Also they lose intensity as they get older. They sell a light meter and it will tell you when you bulbs start to degrade and when its time to change them out. My buddy has one and he says it works out great for him. I have yet to get one. I just go by eye and what the corals look like. You can see when the bulbs get dimmer.... Or maybe it just me...
there is info on line about this I just need to find it again.. My mind is not what it used to be..

 

[melosu58]

Let me know more about that meter if you get a chance

 

[Brenden]

I about bought a meter a while back. The one I looked at you could submerge the sensor in the tank and a reading at different depths. It was around $300. I just could not justify it for use just on my tank.

 

[Brenden]

Found the meter I was looking at.
http://www.apogee-inst.com/pdf_files/qmss.pdf

 

[sdellin]

I have PC ligthing and I've started having a problem with cyano that I didn't have before. My tank perameters haven't changed. Is old lighting that much a contributing factor? Could this be my problem?