Oh and at the 800w or 850w (forget which is correct!) setting I was getting way more light than a new traditional single ended 1000w bulb on a dimmable electronic ballast. I think they're very efficient,so simply dialing back could solve your issue?
I've had mine at LEAST 18" or even closer on the 850w setting. I left them at that height , increased the output to 1000w and ended up with some foxtailing. I'd say experiment, but go slow and be careful. These lights have a very high output I think!
When I was looking at lights I was very interested in those t5 led bulbs. If I need any supplimental lighting I think they would be great! I too was having difficulty locating them though. Thanks for posting the source. I'm lucky enough to be in Canada too!
So...you'll think I'm nuts BUT I ended up getting two new Gavita 1000w DE fixtures complete with bulbs.
I'm running them at 825w ea. and getting WAY better results over my old 2000w set up and I'm already saving 400w. I also removed an led panel that was using 600+w at the wall so I'm saving...
I can tell you I'll never go back to single again. There is no question that the DE are worth the extea money. What about the off brand DE set ups? I'm sure it will compare to the Gavita at about half the cost. If I buy another light it would be an off brand DE. set up.