Going LED to Halide/T5

[CheifReeferNB]

I am in the process of partially restarting a tank and as part of the change I want to switch from LED to halide and T5. I invested in a premium led setup which has been disappointing to this point. I don’t have confidence that the lights themself or the spectrum produced is optimal for coral growth.

That brings me to my main question. What would I need to do to switch to a halide/T5 hybrid setup?

I imagine that a sudden change like that would be stressful to the corals so if anyone has tips or experience with something similar please let me know.

 

[tbrown]

You'll want to mainly ensure the PAR levels don't spike or drop significantly. If the new Halide is significant brighter, you'll risk bleaching corals. If it's a little brighter, no big deal.

The other issue you may run into is a shift in color spectrum from the LEDs to halides (depending on which bulb you select) could cause some different effects with corals. Some might like it better or not like it at all.

Best bet, figure out approximately what spectrum you're running and match that, then start the halide higher above the tank and lower it to get the proper PAR readings.

Watch your corals closely and they'll tell you over a day or two wether they're liking the change or not.

T5s will be the same thing - spectrum and PAR. Those are usually the two main concerns with lighting changes.

 

[CheifReeferNB]

You'll want to mainly ensure the PAR levels don't spike or drop significantly. If the new Halide is significant brighter, you'll risk bleaching corals. If it's a little brighter, no big deal.

The other issue you may run into is a shift in color spectrum from the LEDs to halides (depending on which bulb you select) could cause some different effects with corals. Some might like it better or not like it at all.

Best bet, figure out approximately what spectrum you're running and match that, then start the halide higher above the tank and lower it to get the proper PAR readings.

Watch your corals closely and they'll tell you over a day or two wether they're liking the change or not.

T5s will be the same thing - spectrum and PAR. Those are usually the two main concerns with lighting changes.

The spectrum change is what concerns me most. I’d be going from a blue heavy to more natural spectrum. I don’t know how things would respond or if there’s a way to do it more slowly other than replacing some of the LEDs with T5s and then removing them all for halides eventually.

 

[Mr. Mojo Rising]

I have metal halide and I buy corals from LFS’s and fellow hobbyists that have leds, 30 minutes after I buy them they are in my tank. My corals have always been fine. I usually acclimate new corals on the sand for a week or two before moving them to their forever spot.

I would suggest to start the MH at 4 or maybe 5 hours a day and slowly bump it up to what you want.

 

[tbrown]

The spectrum change is what concerns me most. I’d be going from a blue heavy to more natural spectrum. I don’t know how things would respond or if there’s a way to do it more slowly other than replacing some of the LEDs with T5s and then removing them all for halides eventually.

You can get a 14,000k or 20,000k on the halide or go heavy blues on the T5s also.

When I ran hybrids I went with 10,000k halides and actinic T5s.

 

[CheifReeferNB]

The spectrum change is what concerns me most. I’d be going from a blue heavy to more natural spectrum. I don’t know how things would respond or if there’s a way to do it more slowly other than replacing some of the LEDs with T5s and then removing them all for halides eventually.

You can get a 14,000k or 20,000k on the halide or go heavy blues on the T5s also.

When I ran hybrids I went with 10,000k halides and actinic T5s.

Yeah I was leaning 14K for the halides. The other option I was considering was getting a selectable ballast that would let me start with 150W/175W bulbs and then once acclimated I could pop in the 250s.

 

[Rob A]

I switched from led to T5/ MH the only thing I did was raise the lights for a month and had no unexpected issues. I did loose some zoas that were directly under the MH but I knew that would happen.

 

[X-37B]

Yeah I was leaning 14K for the halides. The other option I was considering was getting a selectable ballast that would let me start with 150W/175W bulbs and then once acclimated I could pop in the 250s.

Just run the halide on full no need to reduce it. I run a 400 20k over my 112 with led 14k bars.
500 par in the middle. Start corals at 250-300 on the edge.
Digital ballasts give me 30% more par.
All the coral came from my led systems with no issues. Tank is just 6 months.
I would opt for led bars over t5's in todays market.

 

[PPBlimpy]

I run new CMH @ 10k and use my old LED as supplemental lighting.
Make sure you can source the T5 bulbs. They can be hard to come by.

Good luck with the Halides, i really like the CMH and put out plenty par but the highest Kelvin bulb is a 10K. takes lots of blue to overcome

I want to swap the Led supplemental for 36" Vho actinics but haven't found a fixture and havent gone down the DIY rabbit hole yet.

Edit: thanks for putting this in my head, found a supply of VHO bulbs and going down the rabbit hole!!

 

[Reefing102]

I’d just switch, not worrying too much about acclimation. I’ve done it a few times with no ill effect. You may see a stunt in growth as the coral gets used to the halide but yea. I just start coral about mid level in my tank (40 breeder) and haven’t had an issue.

I also run Aliexpress blue LED bars instead of T5s but the halides run for 8 hours.