MH vs T5HO, Power Usage and Benfits?

rastaangel

rastaangel

Member
I just sold my paintball gun(FINALLY) and have a bunch of money to upgrading my lighting...
So the time has come to choose between a brand new 8x54 T5HO or a used "need to modify to fit my application" 3x250 MH hood w/6 10k bulbs.
They are about the same price by the time I finish buying bulbs for the T5...
I have held off on getting SPS and clams and what not since I havnt had enough light.
Which would be a better choice? I would have to mod the MH hood cuz its a 72" and my tank is only 48" in order to use all 3 bulbs.
Also how much more power do MH setups consume over T5s? What are the perks of MH over T5 or vise versa?
 
acrylic51

acrylic51

Active Member
Need a little information!!!! What size tank are we talking about..... I'm assuming the MH setup has 3 MH bulbs?????
 
1snapple

1snapple

Active Member
10k bulbs.... well It's just my opinion but I think 14k bulbs look better. I would go with the MH. The MH will do any coral, it requires more power but you can really do anything, expecially with 3 on a 48" tank. with 250w you can do clams on the bottom to.
 
acrylic51

acrylic51

Active Member
Quote:
Originally Posted by 1Snapple http:///forum/thread/382659/mh-vs-t5ho-power-usage-and-benfits#post_3341241
10k bulbs.... well It's just my opinion but I think 14k bulbs look better. I would go with the MH. The MH will do any coral, it requires more power but you can really do anything, expecially with 3 on a 48" tank. with 250w you can do clams on the bottom to.
I agree would probably get better coloration from a 14k bulb. The theory of stuffing 3 250W MH's over the tank is overkill. 1 MH for 2' is generally the recommendation. No real gain by stuffing 3 MH's over the tank. Yes you can keep what you want with ease with 2 250W MH's, so the purpose of 3 is a waste. You aren't gaining anything, but electrical waste and possible heat problems with the tank. On that same note, a good T5 setup with good individual reflectors and good bulbs will give you the same affects and quality lighting the MH's would provide and you could keep what you please including clams and all the other goodies. Nice thing, the heat issue isn't a problem, and less energy used.
 
1snapple

1snapple

Active Member
Ya, i was thinking about the depth to. 90g tank so its probably 28" deep? or 24"? That is a kinda deep and 250w MH would penetrate better then T5's wouldn't they?
 
rastaangel

rastaangel

Member
its 24" deep. The 10k bulbs come with it but i would prob buy 14k when i went threw all 10 10k bulbs
How much heat to MH give off? Would I need to space them above my tank?
 
bang guy

bang guy

Moderator
Quote:
Originally Posted by rastaangel http:///forum/thread/382659/mh-vs-t5ho-power-usage-and-benfits#post_3341384
its 24" deep. The 10k bulbs come with it but i would prob buy 14k when i went threw all 10 10k bulbs
How much heat to MH give off? Would I need to space them above my tank?
MH are more efficient at higher temps so it really doesn't matter how much heat they give off. Generally, since most reef lighting systems are fairly efficient the amount of heat generated is proportional to the wattage of the bulbs.
 
acrylic51

acrylic51

Active Member
Not trying to discourage the use of MH's, but 3 MH's over a 48" is a waste of energy, and excessive heat transferred to the water. The MH's should be mounted at least 12" above surface. Again a MH will cover a 2' square area, so no need for 3.
T5's would provide the same penetration with less heat transfer. So the theory or thinking that you'd be limited to what you could keep is incorrect. A good reflector and bulb combination is more than adequate for SPS and clams....
 
acrylic51

acrylic51

Active Member

Quote:Originally Posted by rastaangel http:///forum/thread/382659/mh-vs-t5ho-power-usage-and-benfits#post_3341402
is 12" really how much space is required? Even with a covered glass top? I would prob only use 2 of them
 
Loose the glass tops on the tank. Stops/slow evaporation and gas exchange that takes place. Yes 12" is recommended again lighting puts off a good amount of heat, and glass lids need to be kept clean, because dirty lids cut down light penetration.
 
rastaangel

rastaangel

Member
I need to keep it covered as I have a huge issue with humidity in my apartment... and having no top on my tank with all tht water movement will release alot of unneeded moisture into the air
 
gill again68

gill again68

Active Member
I run T-5s because I want to. If I had room I would probably run all T12s. Heat, electricity and all. The shimmer is pretty for the MH though.
 
keith gray

keith gray

Member
I have a 4foot long 75 gallon and run to 250watt mh 14k. My DT is open and I have a fan running in my canopy. It provides plenty of light and since I went topless I have had less problems with PH stabilization.
I am addicted to the shimmer of MH and really prefer them, but the "look" part of this is a matter of preference.
 
rastaangel

rastaangel

Member
ok so what if i kept the glass constantly clean? or is it still gonna interfere with the performance of the lighting, which ever i choice to use.
 
keith gray

keith gray

Member
When I had lids the salt creep constantly was an issue. Keeping it clean so light could get through, etc. You need good surface agitation for oxygen exchange etc. Until I went topless I was always fighting to keep my PH up and since then I have had no issues, it really helped.
 
acrylic51

acrylic51

Active Member
You can use the glass lids, bit I'm pretty sure with the MH's your gonna find issues with excessive heat, your hindering a natural process. Curious are you running a sump? Filtration type??
 
bang guy

bang guy

Moderator
Quote:
Originally Posted by rastaangel http:///forum/thread/382659/mh-vs-t5ho-power-usage-and-benfits#post_3341664
ok so what if i kept the glass constantly clean? or is it still gonna interfere with the performance of the lighting, which ever i choice to use.
The issue is that you will have an enclosed box that you are feeding massive amounts of energy into (light & waterflow). The energy from the light and waterflow needs to dissapate or the tank will heat up. It doesn't matter what type of lighting you choose, the amount of energy reef animals require will need some place to go or it will heat your water past the point of tolerance. An open top allows evaporation which is the single most efficient way to remove heat from water.
 
You must log in or register to reply here.
Top