MH Lighting 2x250watt or 2x400watt?

[reeftank250]

I'm upgrading and don't know which to choose. The tanks is a 135 (72x18x24) I have 175 watt MH right now with VHO's. I was thinking of adding 2x250 or 2x400 on top of what I have now or just getting rid of my 175 watt MH. Which should I get? Any help would be great.

[mordibv]

What are u going to keep ?
What color bulbs are you going to use ?

[ihavtats29]

with 175 w a iwasaki 15 k puts out more par than any of the 250 watt bulb/ ballast combos at 87 ppfd and a little over 1 watt of power consumption. the next choice would be 400 watt be be ready for around 5 watts of power usage but ppfd's in the 100's to 200's

check this out

http://www.manhattanreefs.com/lighting

[reeftank250]

What is ppfd? I'm not targeting one specific thing, I would like to be able to keep a little of everything. I was going to use 14K SE the ballast I'm going to be getting is a Hamilton Technology.

[ihavtats29]

ppfd is how par is rated, with wha your looking at you will have a ppfd of 53. you can keep a mix of everything under that but you can get the same from a 175 w setup that will have a lower power consumption

[reeftank250]

so should I do a 175x3? I'm worried about getting enough light to the bottom of the tank. Is it all in the bulb? What is the best bulb to use? I usually use the Hamilton bulbs.

[ihavtats29]

definatly 3 they realy only cover 24'' of tank per bulb , im using the iwasaki 15k's they have more of a 12 k look but im getting great light output and in short time ive been running them im seeing a big diferance in my corals from all the other bulbs ive tryed in all kelven ratings, i was getting very slow growth from my sps untill i was given a used 1. just in 24 hrs all my corals from the softy's to the sps looked much better fuller and healthy after 3 days i started seeing signs of growth from my sps , even the ones that havent shown much of any growth over the last 2 months , if you like the blue look you will have to use suplemental antinic lighting and it looks like you have the vho's allready . i was just dealing with the same question you were asking , untill i saw the data for my self and the results , i was going to upgrade to 2) 400 watt untill i got my hands on that iwasaki bulb,i also didnt want to add a chiller to the system , if you have magnetic ballasts the bulb will not work it has to be on a electronic ballast to fire. its not all in the bulb but the bulb / ballast combo, im using ARO electronic ballasts they run around $90 each and with the iwasaki bulb are getting the same results as the icecap ballasts

[das75]

Being 24" deep should be good with the 250s either 2 or 3.

If able, consider running your VHO along as supplement and dusk/dawn.

[ihavtats29]

here is a pic of the new buds forming over 2 weeks time on my birds nest since being under the iwasaki

http://i2.photobucket.com/albums/y29/ihavtats29/DSCF5217.jpg

http://i2.photobucket.com/albums/y29/ihavtats29/DSCF5218.jpg

[ssamick]

I second the 250's Probably three of them. And sup with your vho

[ihavtats29]

btw my tank is 24'' deep and that sps is at the bottom of the tank,

[ihavtats29]

use the link i posted above and deside for yourself this is mainly going to be a personal preferance on what you are looking for , click on the lamp ballast tab enter the bulb your interested in , leve the ballast info empty and click submit , it will give you the daata for that bulb with diferant ballasts it was tested on.

[grigsy]

Since you already have VHO actinics, I would go with a 10K bulb. You will see better growth from a 10K than higher Kelvin halide bulbs and your actinic VHOs will blend nicely with it.

XM 10K is a good bulb (a bit yellow, high PAR) or Hamilton 10K is also also a good choice (more white, slightly higher PAR)

[ihavtats29]

xm bulbs i have 2 of every kelvin the sell in 175's they are not high enough in par, i personaly was not happy with them , the 10k puts out 62 to 72 ppfd and the higher kelven puts out much less as low as 35 ppfd from the 15 and 20k's

hamiltons range from 19 to 71 ppfd

[cashman95]

SPS....? 400 watt radium here! Would never go back to 250!

[hyperfocal]

I'd go for the 250W with good quality reflectors -- more economical than the 400W, and should provide more than enough light in a 24" deep tank

[reeftank250]

OK, so I go with 250s and a good reflector. The ballast I'm going to get is a Magnetic is this bad? My current one is Magnetic and I haven't had any problems.

[reeftank250]

When it comes to ppfd am I looking for a lower #?

[ihavtats29]

the higher the ppfd the higher your par is, if you want good water penatration you want a higher par, the par output between the 175's with the right bulb will blow away most 250 watt combo's unless its a 10k 250w if your going to buy all new ballasts and bulbs your better off going with 400 watt, if you want lower energy costs and less heat stick with the 175's and the iwasaki 15k, magnetic ballasts are not bad but will not fire some bulbs and they do hum , just like in a warehouse you can hear the lights humming , is from the 400 watt magnetic ballasts , if you go electronic they will fire everything put off less heat and no noise/hum , reflector wise if you have the room under your canopy i recomend the lumenbright reflectors , here is a review on reflectors http://www.advancedaquarist.com/2009/1/review