i cant believe it, another MH post!!

[mastertech]

questions can easily be answered with searches but i have not found this answer.
if MH can last 2500-3000 hrs.
and the generic answer is 6-10 months for life but
Originally Posted by Bang Guy
http:///forum/post/2010660
4 hours a day of intense light is all that most corals require.
You could add some flourescent lighting and keep that on 10 - 12 hours a day and only fire the MH for 4 hours in the middle of the day.
I wouldn't go from 12 hours a day right to 4 hours a day though. I'd suggest a gradual decrease in the amount of time the lights are on.
that is only 1400 hrs of use in one yr. which means that the bulb can potentially last over 1 and 1/2 yrs.
start the argument!!!
(i currently run two 96W CF for 12+ hrs each day and fire one 150w HM at 11:00 until 3:30ish and fire the other from 2:00 to 7:00ish)

 

[scsinet]

I don't see why not. I know I always preach a year on halides, but in the end the rule is flawed because it doesn't take into account lamp hours, which is really what needs to be looked at.
So yeah... I don't see why if you run your halides for 4 hours per day, instead of 8, that the lamps wouldn't last twice as long - assuming though that the "rule" is based on 8 hours.
... of course CFLs last roughly half as long as halides, so if you are putting all hour hours on those... you may actually be increasing your expenditures...

 

[mastertech]

really "half as long" i have read between 4-8000 hrs for CFLs
but i cant find any reputable resorces for this #
one yr at 12 hrs a day is 4380 hrs

 

[bang guy]

MH lamps are also degraded by starting them unfortunately. You would definately get more life from a bulb by running it half as long, but you will not get twice the life.
You will also save on electricity.

 

[flower]

Originally Posted by Bang Guy
http:///forum/post/3173871
MH lamps are also degraded by starting them unfortunately. You would definately get more life from a bulb by running it half as long, but you will not get twice the life.
You will also save on electricity.

Far from an expert...but I agree because I read somewhere that turning a light on and off does more to lower the life of a bulb than just letting it run.
I run my MH 4 hours then off 4 hours than on again 4 hours, because of overheating the tank. Unless I find excess algae indicating a weak bulb, I will just as routine change the bulbs at 1 year...HOWEVER...I keep 1 old bulb just in case of a break, that way I will have something until I can replace it. No store around me carries the bulbs so I have to order it.

 

[scsinet]

Originally Posted by Flower
http:///forum/post/3173880

Far from an expert...but I agree because I read somewhere that turning a light on and off does more to lower the life of a bulb than just letting it run.
I run my MH 4 hours then off 4 hours than on again 4 hours, because of overheating the tank. Unless I find excess algae indicating a weak bulb, I will just as routine change the bulbs at 1 year...HOWEVER...I keep 1 old bulb just in case of a break, that way I will have something until I can replace it. No store around me carries the bulbs so I have to order it.
Keep in mind that halides are not conventional lamps...
I hadn't considered the startup... Bang is probably right.

 

[mastertech]

alright..... i cant find it anywhere. how many average hrs of life are in most aquairum CFLs?
i dont like this general rule stuff. i need something more logical.

 

[scsinet]

There is no set amount, only rules of thumb. While I say that the length of time is flawed, it's because it's not based on any set amount of lamp hours.
However, even lamp hours, as exact as it sounds, won't be accurate because lamp/ballast combinations, lamp manufacturers, ballast manufacturers, line voltage, blah da blah, da blah. The only real way to know for sure is to invest in a meter so you can replace lamps only when they need to be replaced, but almost nobody does that.

 

[bang guy]

Originally Posted by SCSInet
http:///forum/post/3174369
The only real way to know for sure is to invest in a meter so you can replace lamps only when they need to be replaced, but almost nobody does that.
+100
I don't know why this isn't more common. Lamps are expensive and replacing them early is throwing money away and replacing them late is stressing your corals.

 

[mastertech]

Originally Posted by Bang Guy
http:///forum/post/3174512
+100
I don't know why this isn't more common. Lamps are expensive and replacing them early is throwing money away and replacing them late is stressing your corals.
yes but since no-one buys them and everyone uses a "general time span" to replace bulbs. would you not agree that haveing something more specific would be benificial (ie hours of effective life) i have already saved money by not conforming to the generality of changeing my MH bulbs every 6-8 months.
but since we are on the subject, what is that meter that you have/suggest and where do get one and for how much money?

 

[bang guy]

You should be able to get a lux meter for around $20.
My disclaimer is that a lux meter will not tell you how much light a bulb is producing. What it can do is tell you if it's producing significantly less light than it used to.
For example, I'll take a lux reading after running a bulb about a month. After that I'll occationally test it and if the lumens decrease more than 15% from the first reading I'll replace it. Don't take a reading during the break in period, it's not accurate.

 

[mastertech]

Originally Posted by Bang Guy
http:///forum/post/3174596
You should be able to get a lux meter for around $20.
sweet, thanks i will look that up. thats alot cheaper that replaceing bulbs prematurely or killing some nice coral due to under lighting.