View Full Version : Differences between SE and DE metal halide

05/10/2006, 08:45 AM
I want to know your opinions about the differences between DE and SE metal Halide.

I know that the DE should be shielded and that cuts down on par and the DE is smaller.

Does either one produce more heat? What else are some differences?

Or does it depend more on the ballasts? I'm thinking about a coil and capacitor for the SE or an Electronic for the DE. How much more heat can I expect out of the coil and capacitor? Does it consume a lot more electricity? Is there any more of a fire hazard with either one?

I'm just tring to figure out which one I'll be happiest long-term with.


05/10/2006, 09:31 AM
SE bulbs are shielded too, they are just inside of a glass envelope. Check out Sanjay's site for all of the information you will need.

05/10/2006, 09:39 AM
First off neither is inherently "better" than the other but rather it really depends on application and setup parameters. SE bulbs are larger therefore it is more difficult to make a space effecient, effective reflector. Also you have issues with starting mechansims--ie probe vs pulse start bulbs. As a generality you sill get lower peak light levels but better spread with SE bulbs. B/c of the different starting mechanisms among SE bulbs and the relative ineffeciencies of probe and pulse start ballasts I personally prefer electronics with SE MH. The best reflectors for SE are the lumenarc 3 and lumenmax, but they are ginormous.

DE MH has slimmer bulbs that allow for a more effecient and compact reflector but it narrows the spread and really makes for a "hotspot" directly under the light. The best pendants light up a 2x2x2 area really well, but it REALLY falls off outside that and because of the "focus" you can hav shadowing issues. The other thing is that these bulbs are made to run on "HQI" baqllasts which have the same effeciencies as electronics but run at higher wattages so generate more light ( ie 250w mag HQI is really more like 300w). The best pendants are the Reefoptix III+ and the "new" PFO mini. There are also claims that DE bulbs are more robust (ie longer life) than SE. Finally 400w DE is somewhat problematic IMO as the bulbs tend to be not so robust and the output numbers on the bulbs aren't so impressive

IF your tank breaks up nicely into 2x2 sections then DE can be a good option for you. If your dimensions demand more spread from your lighting then SE is better. Example: my previous tank was a standard 180--3 250w DE did a great job lighting it. Current tank is a 10x3x2h 450 and 3 400w SE in lumenarcs do a good job IMO

05/10/2006, 10:08 AM
First off neither is inherently "better" than the other but rather it really depends on application and setup parameters.

05/10/2006, 10:15 AM
Maybe if I told you about the tank you can help better.

The tank is a standard 75 gallon, so 18" x 48". I already have 4 -96 watt PC bulbs on it and was thinking about adding a 150- 175 watt metal halide to each side.

My biggest concerns outside of the tank are electricity consumption, heat, and fire hazard.

I have two coil and capacitor ballasts that I could use, but to be truthful they kind of scare me. They just look like a fire waiting to happen.

Someone also mention T-5's. But I don't know much about them and am trying to read the threads on here to learn as much as I can.

05/10/2006, 10:42 AM
If you are going to spend the money don't bother with 175W, a waste of money IMO. I have used both types of bulbs over the years and prefer DE. If you use a good reflector you don't get a hot spot. The only thing that I don't like is changing the 250W DE bulb. It fits rather snugly into the ceramic receptacles. I have never broken one, but I cringe everytime I have to do it.

05/10/2006, 12:38 PM
250W DE reef optix III pendent with a Ice cap ballast. do some searching you will see that , that is one of the best set ups to get plus the difference between SE and DE has been discussed allot. do a little searching through some pages. Send a little money and you will be much happier. good luck