MH knocked out by T5?

I need some help from the T5 lighting experts on this one.

My dilemma is this, I've been running a 250 watt MH with PC actinic for awhile now and I am now testing a T5 system over my tank to get some comparison. It's a 6 bulb light:

AquaticLife LLC | Live It Today! Premium Marine Aquarium Products
36" model

It's an amazing fixture, but my problem is my tank is so narrow front to back that only five bulbs actually hit the display area. My tank is about 13" deep. What I'm wondering is, will that be comparable to my 250 watt MH?

After one day of running it here is my corals opinions of the light:

Acros-Not extending as far
LPS- Looking extremely happy

I want to give this fixture at least a full month test run to see what kind of SPS growth I get, but if this isn't going to be enough light right off the bat, I don't want to start losing coral.

 

No experience with the fixture but on a 13" deep tank if it's a good fixture with good bulbs and good reflectors it should perform as well, if not better than a MH.

What bulbs are you using, and how far off the water is the fixture?

Just keep in mind that the lighting from a single point source like a MH is quite different than T5, more surface area of your coral could be getting more light because there are less shadows. On top of that the color spectrum almost certainly changed so your coral will need to adjust to that too possibly.

Just some ideas.

 

It has German bent individual reflectors that are supposed to be as good as it gets. I worked in a lighting testing facility years ago and from looking at them, I would say they are definitely very well designed reflectors.

It came with 3 10k and 3 actinics.

The light sits about 6" off the water, but I could reduce that to about 2" if that would be a huge difference.

I have noticed the huge difference in the way the light hits the water compared to MH. I'm not sure if I like it yet, but I can see how some people would definitely prefer the look to MH.

I think I'll keep the light on the tank for further testing. If all else fails, I have frags of all my SPS on frag racks about 4" underwater, so they should get plenty of light to stay alive and re-stock my tank if need be.

Thank you for the reply.

 

I agree with Screwtape. I would say with confidence that if you were to add higher quality bulbs like ATI or Geissmann and have good fans and at least 3 of them were blue+ you'd be throwing more PAR to the bottom than your MH at 13".
My tank is 16" depth with a 6 bulb fixture. 3X ATI Blue+, ATI 12000k Blue special, UVL 75/25 actinic white and GE 6500k. I can grow any sps and when my params stay consistent for a few more months I'm gonna try a crocea.

 

Yes, usually stock bulbs are not that good. I have no clue what the enw AL t5ho's put out for PAR. I do know the ATI's are tops of the PAR game for t5 bulbs.

Now t5ho vs MH, they are different, even if PAR is the same between the 2 fixtures, t5ho being linear and not a spot source of light really allow the corals no shading from the light. Some things do great under t5ho, and other things not so well.

That's why I run 2x250 of MH AND a couple 80w t5ho tubes on my tank.

 

I'm not sure I would necessarily trust any reflector slapped with the label "German". I don't know a ton about it but I doubt there are any regulations about what that actually means or how it can be used, but that sounds like it could just be marketing fluff (although obviously not necessarily). They might be great reflectors but it would be nice to see how they perform with good bulbs in them. They're probably OK as long as they're individual reflectors though. I don't think you'll have any issues once you get good bulbs in there.

Not to be too repetitive but unfortunately like was said before some of the stock bulbs are horrible, for example the ATI Blue Plus lamp is a blue range bulb and has more PAR than the Current USA stock daylight lamps. Not all of them necessarily are though just something to be aware of that you might get better performance from well known quality brand bulbs.

Also I wouldn't worry excessively about your SPS dying, if they start to brown out from not enough light you will probably have plenty of time to get new bulbs or try to fix things. A lot of Acros (unless they're really sensitive or are unhealthy already maybe) will not just up and die on you if they don't get enough light for a period of time.

Just keep an eye on the SPS colors and if you notice a lot them dulling significantly or turning brown you might have an issue, that is of course as long as all your other parameters stay stable. Give them at least 2 weeks to get used to the new light I would say as long as you don't notice any obvious problems.

 

Sounds good. I'll look into some better bulbs in the future. It seems like today the corals are looking much much happier, so after some time I'm hoping they will show some growth under the new light. Thank you for the help everyone.

 

A small update:

All corals look happy under the T5's. I think I'm really starting to like them now. I still miss the shimmer of halides, but the reduction in heat and end to end full lighting is a nice change.

 

hey mike, check this out:
par (tfivetesting)

 

LEDs give you a shimmer effect.. you could add a strip or a few white/blue leds for shimmer..