Reef lighting for a 20g long

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Agnate80700

Aquarium Advice Freak
Joined
Jan 5, 2007
Messages
260
Location
Canton, MI
Hey folks. Before my question, let me explain my situation:

I want to upgrade my lighting system.

Ive got a 20g long (and about double that in filtration volume) and I have a PC 130w lighting system on it (6.5wpg) and I want to do clams and sps. I have experimented and put a birds nest frag in and a small clam, and both seem... ok, but not really thriving. Add to that, I've never really been thrilled at the way PC light looks. I used to have a 150 gallon system with a 1030w MH system on it, and compared to how that looks, well... I think I was spoiled.

I found some great deals on ebay for some HQI light systems. There are two options: a 250w and a 380w system.

Questions:
1) Is 250 or 380w on a 20 gallon long too much light? (Thats 12.5 wpg or 19 wpg respectively) I think I'd be ok with the 250w but I'd like the added flourescent lamps for more even light distribution... but Im thinking 380w may be way too much.

2) Would a MH system with one lamp in the middle of the rig distribute light properly? Thats how they tend to come... just the one bulb in the middle. Wouldnt that trasnlate to a blast of light in the center of the tank and dark spots on the ends? Or am I mistaken?
 
Dude, seriously, way overkill. At most I would just use a 70w halide since a 20g is so shallow and halides are used for their superb penetration beyond 24". You'd even be fine with a nice T5 setup. Your dims are what, 36"x12"x12" or something like that?
 
30x12x12 I believe. I realize the wattage is overkill, but it become an issue of cost.

For some reason, a 150w 30" system is minimum $300 but a 24" 380w system is $180. I dont really care about name brands, and I think thats why... there are a lot more off brand people making 24" systems with a ton of light than there are making 30" systems with reasonable light.
 
now that im looking at it, Im really leaning toward the 150w hqi system. thats just shy of 10wpg and that will make everything very happy I think. $235 shipped.... seems to be a good price too
 
Sorry, but sometimes Brand makes all the difference. If you get too much light you'll nuke the system anyways. If you are dead set on a halide then I would grab two 70w or a 70w and 150w unit. Something like this: http://www.reefgeek.com/lighting/Metal_Halide/Sunlight_Supply/Reflectors/Reef_Optix_3_Plus_HQI_Reflector_%28150W%29_by_Sunlight_Supply

and JBJ K-2 Viper HQI Clamp on Lamp Lighting Fixture something to that affect.

I guess you could just get two of the 150w units and situate them higher.
 
Dont think the link to that first one worked... and the second one, I would get that but a) I'd want two, so $170x2=too much $$ and b) I still would like some actinic lighting in there.

I realize I can nuke everything with too much light but at what point is too much? I mean, there are reefs in nature that are only inches or a few feet below the surface and god only knows what the wattage of the Sun would be comparatively... and those coral are obviously just fine.

is 10 watts per gallon an ungodly amount? Or is that within the acceptable range? What about 12 watts per gallon?
 
Ten and 12 are too much. I personally think that what you have right now is enough but James gave you a good other option. I cant see you going any higher than what he gave you. If you are determined to go MH I would go with what he suggested and not higher.
 
Too much intensity for such a small and shallow tank. You are going to burn up alot of corals with that much light and intensity. BTW I`m moving this to the General Hardware and equipment discussion forum.
 
Well, ok heres my issue: I dont think my PC lighting is making the higher-light requirement coral/clam happy. The coral themselves seem to be ok, but the color seems to become more blah over time from when I got them home from the store. My old tank, which had the 1030w MH system on it (running @ 7w/g) didnt seem to have that problem. I assume that was thanks to the MH which has better light output than PC, even at the same wattage.

My budget is $250 at the very most, preferably $200, so the two 70w vipers are out. Would I be better off at looking for a T5 HO system that puts out like... 130-150ish watts? And if so, is there any hope of finding a system that isnt a fortune?
 
Definitely more intensity. As far as intensity it goes PC`s---> VHO`s ---->
T5`s ------> MH`s. It`s not about WPG anymore. That has become outdated. I only use it as a broad guideline for explaining to new folks. It`s all about intensity and par now. That`s why I`m trying to tell you about going too bright because it`s not about WPG but intensity. I hope this helps.
 
Ok, yes I see from googling around this 'PAR value' thing. Interesting considering I the last time I did any sort of intense research for lighting was only about two years ago.

So I suppose a 6x24 T5 system would do nicely? Thats 144w total.
 
Question:

What would the PAR percentage increase be going from 130watt PC system to a 96watt T5 HO system? Are we talking like... 10%? 50%? -25%?

What about a 144watt T5 HO system?
 
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