Metal Halide VS VHO - Longevity

[xkenneth]

Hi,

So i'm getting ready to start cycling my 45 and i've been considering what lights to get. The tank is 36" by 18" and the two options i've been considering are Metal Halides and VHOs. For a Metal Halide setup I could get the ballast for a 250W bulb for about $85, i'm sure the fixture would amount to $15 or so, and the bulb for about $100. So that puts me at an intitial cost of $200 to set up a Metal Halide system (Not including the hood i'll build). On the VHO side I can get an Icecap 600 and the fixtures/mounting for $100 from a friend even. Now the bulbs appear to cost about $25 give or take and i'd be doing 3 96 watt bulbs, 1 50/50 actnic and 2 10k white. That puts at an initial cost of $175 for the VHO's.

Now looking at some of the hour ratings on these metal halides the average life seems to be about 7500 hours, which means if I have a 12 hour day cycle that would put me at 1.75 years per bulb or for an 8 hour cycle
2.65 years per bulb. So just to take an estimate let's say 2 years per bulb. So $50 a year physical cost (not electrical) for metal halides. It seems you need to replace VHO bulbs about every 6 months so that means $150 a year for 3 bulbs in my case.

My question i suppose is, am I looking at this correctly? Are Metal Halides really the more cost effective solution? Or does the power consumption even it out? My friend also suggested some other configurations, perhaps one metal halide and an actinic together. Please let me know what your take is on this.

Regards,
Ken

 

[tecwzrd]

Either way the electrical cost will be close. As far as when to change the bulbs you are correct that VHO should be replaced about every 6 months but also consider that MH bulbs should be replaced once a year to avoid algae issues.

One MH 250W bulb is going to roughly cover 24” so the ends of your tank will not receive as much light as the middle.

Is your tank a 30 Breeder that is 36 3/16 x 18 1/4 x 12 15/16? If so then the MH light may be too intense considering the 12” high and I would go with VHO if that is the case.

 

[sir_dudeguy]

So i'm getting ready to start cycling my 45

i dont think its a 30 breeder, lol just kidding.

but ya, i think mh's last a bit longer, but you do get the un-lit part on the sides if your tank is too long. so what you could do is get 2 smaller wattage ones and space them out across the tank.

 

[tecwzrd]

I know he said 45 but most 45 gal tanks are 36 1/4 x 12 5/8 x 23 ¾ so I’m wondering what the total H/W/L is on this tank.

A 30 Breeder is the closest I can think of to match the 36” long by 18” wide.

 

[Hara]

The VHO bulbs made by URI are good for a year.

 

[xkenneth]

And they avoid spectrum loss? The tank dimensions are 36.5" wide, 18.5" deep and 17.5" tall measuring on the rims. After these comments and just some more thought the VHO's seem to be like the better idea. Is there any way I can easily measure the spectrum they're putting out so I can know when to replace the bulbs? Or will it just be apparent by algae growth and other tank changes?

Regards,
Ken

 

[Hara]

The URI bulbs are pretty consistent in their "lifespan". I have used them for several years now. Most other bulbs are 6 month bulbs. You cannot really eyeball for color shift and the meters are quite expensive. I use the "calendar" method

 

[seaham358]

IMO 6-8 months is a good time to change the bulbs out. I use the URI also and I notice algae issues when my bulbs start to get older. My frined has the meter and he says that the bulbs start to drop out alot after 6 months.
I push mine and run them 8 months to try and save a few $$. You can't go wrong IMO with the VHO lights, they give the tank a nice look.