Going back to Metal Halides from LEDs

Discussion in 'Equipment' started by Vincerama2, Nov 21, 2016.

  1. sfsuphysics

    sfsuphysics Supporting Member

    The largest benefit of halides over LEDs (of any fixture) is that with a good reflector you're basically going to to get one big spot light of light that shines into the tank, it's going to hit corals from multiple angles, it's going to light a big area, and for aesthetic purposes any shimmer will be uniform in color and not all color seizure inducing.
  2. Franko

    Franko Guest

    Sorry to hear that you are having troubles. "Why is my stuff dying" is the question all reef keepers have had to face and all fear having to ask again.

    Before dropping coin on metal halides and going back to the dark side, try everything you can to improve water chemistry. One thing I noticed you said in your post is that you did water changes to correct for low magnesium. In my experience water changes are good for cleaning up water but not good for bringing water chemistry into alignment. If something is really low (Mag, Cal, Alk) doing a water change will help a bit but it is really no substitute for dosing. Whatever parameter was low before the water change will be low again a day after the water change. So buy some:

    Start dosing this stuff by hand every couple days and measure to make sure everything is where it should be.

    Also get some:

    Amino Acids are something corals need and if you are doing a lot of water changes Amino Acids are probably very low.

    Good Luck!!!
    Newjack and Yippee like this.
  3. sfsuphysics

    sfsuphysics Supporting Member

    Yeah first and foremost I'd test anything and everything you can first to see if there are issues there, and that includes your temperature and how it fluctuates over time.

    Second you say your lights are Kessil 150s and 150W MH pendants. How many are we talking about? The Kessils by themselves I would call accent lighting on any tank that is 24" tall (or more), the 150W pendants, I'm assuming you have a good shiny reflector, well again they're not going to give that much pop. Just to throw out some comparison type of numbers of other reefers, when I ran my 180g tank (4'x3'x2') I had 2-250W MH bulbs with lumenarc pendants and 4-6 T5 bulbs (can't recall the total amount it was a while back) with icecap (or similar) reflectors. Kris (Pacifica), has a ton of Kessils over his tank (I want to at least 7?) but they're the 350 and 360 Kessils now his tank is a bit bigger than yours, but not terribly much, but he has them spread out everywhere.

    Third if you're going to upgrade, go to 250W halides, a jump to 175W isn't a huge leap and unless you're really worried about electricity wouldn't be my call on something to do. I would rather have 250W bulbs on 6 hours a day than 175W bulbs on 8 hours a day anyways, and then use supplemental lighting during the other time (in fact on my 180g tank, I want to say I only had my MH bulbs on for about 5 hours a day)
  4. Yippee

    Yippee Supporting Member

    In his first post he states Kessil 150s and 150 watt LED pendants. I presume he meant 150 watt LED panels. More confusion to the pot....lol.
  5. Vincerama2

    Vincerama2 Evil Overlord

    You know what, maybe they are 350s and not 150s... oops.

    I'm going to swap in my 175, I have two from my old tank, and somewhere I have a brand new ballast and a used reflector.

  6. Newjack

    Newjack Supporting Member

    I have a hamilton dual 175mh with T12 actinics. 4 foot hood/ encloser. All bulbs work, you're welcome to it if you like. pm me if interested
  7. Coral reefer

    Coral reefer President

    Wait, seriously? Not sure if they are 150 or 350? Figure that out and borrow the par meter
  8. Coral reefer

    Coral reefer President

    Wait, seriously? Not sure if they are 150 or 350? Figure that out and borrow the par meter
  9. Vincerama2

    Vincerama2 Evil Overlord

    They are 350s. I knew that, but brain farted when I wrote 150s.

    Anyway, I spent some time swapping in the old 175s in. So one both sides I have the halides, in the center is the Kessil 350W. The MH are super yellow in comparison, but the bulbs are old and I'm going to probably put in some 14ks.

    I've tried a bunch of things to "fix" the tank and this is the last variable. I ran my 58g for 15 years and everything (especially aiptasia) grew in it, so let's see what happens now. At least I can eliminate the lights as a variable now. Power usage will go up again, and wife won't like that. I'm resisting swapping the central light for a backup MH ballast that I have sitting around.

    And yeah, I'll borrow the par meter if I can make it to the pot luck.

    Sadly one of the kessils went and fell into the tank, so I rinsed it in fresh water and am hoping I didn't just flush $400 down the toilet.

    I'll let you know how it works out.

  10. sfsuphysics

    sfsuphysics Supporting Member

    throw it in a container of rice, it's a natural desiccant and will absorb whatever moisture it can.
  11. tankguy

    tankguy BOD

    I was reading the responses and from personal expierence MH 150w do next to nothing for sps color. When I switch to 250w 20k is when I really saw the difference. Again I would invite to come see my tank and it's color with the radions I'm using. Very happy with them. And that coming from a big MH fan
    Coral reefer likes this.
  12. Hey Vince, I've been having a similar experience in my 3' deep 225 where I've been getting color fading in spots and then slow wasting away of chalices; also have had some euphyllias slowly wasting away. The tank was great to start when I set it up about 5 years ago running 4 x AI units about 12" off the top, but slowly over the past several months have been having these problems. After running a variety of water checks and supplements, I was advised that LEDs do waste away over time and experience color shift - especially the ones that had only two or three types of colors in the fixture. It may be that one needs to change out the bulbs / pucks every so often on LEDs just like other lights, but I don't have any data on the optimum frequency to do that.
    Newjack likes this.
  13. Vincerama2

    Vincerama2 Evil Overlord

    Thanks Newjack, I think I'm good for now. We'll see how things work out!

    Newjack likes this.
  14. Vincerama2

    Vincerama2 Evil Overlord

    Well, I do like the much lower power consumption of LEDs. Maybe I'll just wait and see what comes out. These Kessil 350s maybe long in the tooth, I bought them off a fellow aquarist/coworker who only used them for a year. but I'm sure the newer fixtures are better now. I don't know. I do know that MH lights you just swtich the bulbs and they are good again. So I'll stick with them for now to see if it makes any difference at all. The central light is still a kessil 350w.

  15. Vincerama2

    Vincerama2 Evil Overlord

    Well at least I found a use for that brown rice that the kids refuse to eat.

    Franko likes this.
  16. Flagg37

    Flagg37 Officer at large

    Ha ha.

    If you really are trying to test the LEDs vs MH, you may want to change the placement so the Kessil is on the end. You might be getting too much light from the MH's spilling over to give an accurate idea of if the Kessils are to blame. Just a thought.
    Newjack likes this.
  17. sfsuphysics

    sfsuphysics Supporting Member

    There's an art to rescuing wet electronics. First if the light was on when it was dunked is probably dead, second rinsing off is actually good since the salt can corrode, third the rice's ability to absorb depends upon the nature of the starch (i.e. instant rice will absorb much more water than regular rice, not sure where brown rice fits on that scale but IIRC it takes quite a while to cook brown rice compared to white), last don't rush things, a week would probably be best, feel free to shake the light after to see if any water comes out... here's hoping you didn't screw up your light.
    Coral reefer and Newjack like this.
  18. Vincerama2

    Vincerama2 Evil Overlord

    I've put in my request for the par meter. the Halides are to either side, and the Kessil 350w does throw quite an arc of light, which I can see as the halides are on a timer that comes on a bit after the remaining central LED. But once I get the par meter, I can of course test each light one at a time, and also just hang the non-submerged LED fixture back up (the 250 non-w) to see how it is. It should be an interesting test.

    I've ordered new bulbs for my halides too, as the kids are protesting how yellow the old Ushio 10ks are. Thank goodness for black friday!

  19. Newjack

    Newjack Supporting Member

    I just dropped off the PAR meter with BOD @ Geneva.
  20. rygh

    rygh Supporting Member

    It depends a lot on the LED and the fixture.
    A good quality LED, driven well below max current, with a proper heat sink, will last an absurdly long time.

    A good list of failure modes is here:

    What we generally need to worry about:
    1) On a cheap white LEDs, driven at current near max, the phosphors can yellow and degrade pretty quickly.
    Not uncommon in a cheap imported fixtures. It saves cost to do that.

    2) Many UV LEDs had a real issue with degradation of the lens, some still do.
    So a "full spectrum UV" fixture, can be suspect.

    3) Heat
    A lot of fixtures have rather poor heat sinks, and fans that clog with dust quickly.
    Some fixtures combine very hot MH lights.
    All that can kill LEDs pretty quickly.

    4) Dirt
    Since LEDs are so low maintenance, we forget to clean them.
    Lenses and fixtures can get a lot of crud on them.

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