From 250W to 400W

[jsousa]

I've decided to upgrade my lighting from 2 250w Radiums to 2 400w Radiums. I feel like I will get better coloration and overall better growth.

Anyone have any advice on transitioning? I'm worried about shocking the corals. Currently I run my halides at 6 hours a day. I'm thinking of reducing to 2 or 3 hours a day and slowly increasing back up to 5 or 6 hours over the course of 2 weeks. Anyone have any input?

 

[Alex T.]

What ballast will you be running the 400 watt Radiums on? Believe it or not, some 400 watt ballasts are terrible for the Radium and in some instances the 250 watt Radium will outperform a 400 in terms of PAR. This is a big determining factor as to how to proceed. Also, what reflectors are you using?

 

[tkeracer619]

I would reduce the photo period and raise the lights.

 

[jsousa]

What ballast will you be running the 400 watt Radiums on? Believe it or not, some 400 watt ballasts are terrible for the Radium and in some instances the 250 watt Radium will outperform a 400 in terms of PAR. This is a big determining factor as to how to proceed. Also, what reflectors are you using?

I'm using 2 Lumatek Dimmable 250w/400w units. The reflectors are Lumenarc Minis.

 

[smalltime]

I run the same ballasts and did the switch from 250 to 400 radiums also. I just shortened my photo period and slowley raised back up. The heat coming off a 400 is a lot more intense. My chiller kicks on a lot more now

 

[rtbm]

If you really want to get the most out of your radium 250's I would strongly advise just going all in and getting m80 ballasts. I know it's a tall order

but

I think you will be very satisfied with the results.

The radium 250's on m80 ballasts are a winning combination.

 

[jsousa]

I run the same ballasts and did the switch from 250 to 400 radiums also. I just shortened my photo period and slowley raised back up. The heat coming off a 400 is a lot more intense. My chiller kicks on a lot more now

Are you happy with the results of the move from 250 > 400? What did you shorten your photo period to from?

Right now, I do about 6 hours on the 250s. What do you think I should reduce the period to and then over what period should I ramp back up to normal?

Besides the chiller kicking in more, do you have any regrets? Better coloration with the 400s and casualties from the move?