I have the 20" 2 bulb one for my ten G. I also bought from the same people, a "set" of 2 bulbs for it(came/w 2 6500K) and
didn't think about it at the time but should have got 2 Roseate but got instead one each of Roseate and 6500K. That is how
I like to use them...one of each of those. Had I got 2 Roseate I would have had 2 "sets" of one of each type bulb.
I like the fixture and so far the bulbs but have not had them long yet to recommend it with any confidence.
I did have a thought though about your bulbs going out so fast. I think you wouldn't let water splash on them so that
leaves a bad electronic ballast or mechanical whichever it is. Curious as to how long mine will hold up. The T8's they replaced
were on there a long time but the current fluctuates quite a bit here as I can watch the bulbs go from bright to a bit less when
the A/C compressor turns on or other things influence the current in this house. Been here for at least 5 yrs and haven't seen
any other things go out prematurely but who knows...
You might be able to get to them through this link. Later when $ gets better(can't resist the idea that if it cost more it's got to be
better) I am thinking of getting a True Lumen plant bulb to go/w the 6500K as the TL is rated for the actual 6700K which is said
to be best for the plants(all the Odessy bulbs longer than 18" are rated for 6700K).
2X T5 Light Bulbs 18 Watts 18W Lamps Aquarium Lighting Fits Most 20" Odyssea | eBay