VHO bulbs

rdaled · 10-17-2006, 01:19 PM

How often do they need to be replaced? What are the determining factors that indicate they need to be changed?

hng · 10-17-2006, 01:27 PM

They tend to lose intensity and change their color over time. Actinic bulbs do this faster than daylight bulbs. The use of electronic ballasts will also proling the life of the bulb. You can tell when a bulb needs to be replaced with a lux meter, looking at coral health, or just changing them on a schedule. Personally, I change daylight bulbs every 12 months and actinic bulbs every 8 months. I use an icecap ballast as well. I might be using the bulbs a bit long, so I wouldn't recommend exceeding 12 months with any vho bulb.

rdaled · 10-17-2006, 07:31 PM

I have (4) VHO bulbs over my 52 gal tank. It is a custom canopy that holds (2)46.5", (1)36", & (1)24" bulbs that are run by an IC electronic ballast. I keep softies and LPS.

Currently I have it setup like this:
(2)46.5" - 50/50 Actinic White's 12,000k (110w)
(1)36" - Daylight Aquasun 10,000k (95w)
(1)24" - Super Actinic 420nm (75w)

I am going to order more bulbs but was wondering if I should change the way I have it configured. What do you think would be best for coral growth?

Geoff · 10-17-2006, 08:23 PM

bulbs for coral growth and for colour are two different things. if you want growth go with all daylight or 6.5K bulbs if you want colour go with more actinics.

if you want more growth get rid of the 50/50's and get more daylights.

G~

rdaled · 10-17-2006, 09:07 PM

Thanks Geoff!

So how about (2) 46.5" daylight's 10,000k
And then the other (2) super actinics

Or would you go with (3) daylights and (1) actinic?

I know alot is preference but I want my softies & LPS to grow and be healthy more than anything.

rdaled · 10-17-2006, 09:15 PM

I guess the lowest kelvin they make in a URI bulb is 10,000. But going from only one daylight bulb to 3 or 4 should make a big difference... I hope.

Geoff · 10-18-2006, 09:01 AM

it will make quite a bit of difference.

G~

hng · 10-18-2006, 09:32 AM

I would take it slowly. I think that a daylight bulb will pu out way more light than an actinic. You probably don't want to suddenly change to all daylights. I would do this, switch to 2 aquasun bulbs (46.5 in), 2 actinic (36 and 24 in). This will give you a nice bluish white light, which I like and probably a bit more light than you currently have. You could add change the 24 in bulb into an aquasun or 50/50 in the future if you feel like you're not getting enough light. I've grown to dislike the pink color of the URI 50/50 bulbs.

rdaled · 10-18-2006, 10:42 AM

Thanks for the help!