Is 1000 watts of light for 100 gallon too much?

[travis_]

I have 2 x 400 Watt metal halides and 2 x 96 watt power compacts installed in the hood on my new 100 gallon corner reef tank. Do you think this is too much?

Should I stagger the start times of each? If yes, how much?

Appreciate input,

Travis

 

[danno14]

Not too much for most corals, but could be too much for some.... what do you wish to keep?
staggering on/off times is beneficial in many ways, but some aspects are not exactly measurable.

 

[nsamouroux]

I'm in the same boat as you We've got a 100-gallon acrylic setup (with an additional 30 gallons of sump and 10 gallons in the above-tank refugium) under two 400w halides (20k) and a 250w halide (12k) in between them for a total of 1050 watts of halide-only lighting. Everything has been doing amazingly well so far once it got acclimated, although we have primarily softies and LPS plus some pocillopora. Our sun coral only comes out once the lights turn off (of course), and the cleaner shrimp / fire shrimp spend most of the day hiding, but everything else seems fine.

We have the center 250w halide come on at 6:30am and turn off at 7:00pm, the two 400w halides come on at 8:00am and turn off at 6:30pm to provide some sort of "natural" transition between full lighting and darkness.

Our main issue was heat with the all-halide lighting, but three LARGE 12vdc muffin fans took care of that and we haven't needed a chiller yet. These three main fans are on the same timer as the 250w halide. Daytime temps stay at 80F, night temps are at 75F with the heater. We also have another large 12vdc fan above our refugium since it is lit 24x7x365 for macro growth which helps evaporation and cooling.

Lots of people online recommend a certain number of watts per gallon of water, but I've found that to be pretty worthless. Your 400w lights should have no problems at all reaching the botton of your tank, and if there's any lower-light corals you can always put them between the two halides or at the edges in or near the bottom. That's what we ended up doing with our sun coral (stuck it in the sand bed under a rock overhang).

 

[Maxx]

Depends on what bulbs you're running and what you want to keep.

Nick

 

[travis_]

thank you for your replies. I am am going to have mainly SPS, a few LPS, softies and clams under these lights. The SPS up high, clams too, and the LPS a little further down and softies in the lower light areas. I have a pentagon corner tank that is fairly tall so based on your replied I have proceded and installed the lights (I had them anyway) with 12K bulbs. I will update on the results.

I found some outdoor timers that can adjust for sunrise/sunset of various locations. I am using one on my shallow tank downstairs set for Florida rise/set. I will use 2 or 3 of these and offset the start times.

 

[burning2nd]

no such thing as to much... but do you enjoy battling temperature problems?

that will surely be a pain in the A$$ to keep cool...


to much... no

overkill ... yes

 

[Myteemouse]

I'm running one 250w 20k MH
2x 96w PC one atn one 50/50 over a 29 gallon!
plus moon light with three timers!
moon lights one 530am off 830am
again at 7pm on off 1130pm

pc atn on 7am off 8pm
pc 50/50 & MH on 9am off 530pm
two 4" computer fans on top of the hood one oushing one pulling and I'm holding right at 80 ALL day w/MH and 78 all night!

 

[travis_]

no such thing as to much... but do you enjoy battling temperature problems?

that will surely be a pain in the A$$ to keep cool...


to much... no

overkill ... yes

I already have the might and bulbs so I am going to go ahead and install it. I will start off with only having it on for a few hours at noon. I have 100 gallons in 5 tanks in my unheated basement, so the majority of hte year the heat will be helpful. Even in summer the temperature would only be around 60 degrees in the basement, maybe 70 max. So I don't see temperature control being a big issue if I have this light on for short periods mid day.

thanks,

 

[OwenInAZ]

I'd say not too much, but I'm biased... 2x 400W over a 90 tall. You'll need to acclimate the corals to that much light, but that's not hard if you start out running for a few hours a day and just moving it up from there until you hit your desired schedule.

In terms of heat, try running them at night. Lots of people here in Phoenix do that, and many of us don't even need a chiller even in summer.

 

[ULTAQUARIUMSVCS]

Hi all

i think for smaller tanks under50-75gla wpg is effective but when u got alot bigger it doesnt matter as long you have a good amount its more like placement, i hav a 600gl tank that had 3 1000w i been slowly changing then to 4 400w actually corals seems to be doing better with the 400 watters. So not always is bout wpg.

Thank you

 

[burning2nd]

take it from me... not acclimating your tank is bad...

it will bleach your coral and reek havoc on your tank...

acclimate slowly.. and you will be fine,

 

[ULTAQUARIUMSVCS]

take it from me... Not acclimating your tank is bad...

It will bleach your coral and reek havoc on your tank...

Acclimate slowly.. And you will be fine,

i know been doing this a while but thanks i have only changed one so far.

 

[veralteaquatics]

Not true, you can have too much light and 400's on a 100 tank is way over kill on light, a waste of electricity and a huge battle with heat issues... 250's would be more than enough..Best of luck

 

[travis_]

Well, belive it or not right now I have 400 watts over my ~ 10 gallon shallow tank and it is doing amazing! The tank is only 8" deep but is 24" x 36" so has as much surface area as much larger tanks. This tank is hooked up to my system of tanks and so far the heat had been helpful to maintain temperature. I will let everyone know how I do with my 1000 watts for 100 gallons.

Not true, you can have too much light and 400's on a 100 tank is way over kill on light, a waste of electricity and a huge battle with heat issues... 250's would be more than enough..Best of luck

 

[crazzyreefer]

I ran (3) 20k 1000w on a large tank, the 20k bulbs were more like 14k visually, Now 1000w is too much, believe me I tried them on other tanks, in fact algae wouldn't grow and just was bleached out, I used them to bleach out corals to hand color them.. Now I had the bulbs only inches from the water, if you ran them 2 ft a way I don't know of the results. but your also talking about 400w bulbs, you can stagger the run time and not bleach your corals, running 1000w bulbs will...

 

[jezzeaepi]

Not true, you can have too much light and 400's on a 100 tank is way over kill on light, a waste of electricity and a huge battle with heat issues... 250's would be more than enough..Best of luck

Yes, this.

 

[mcvicker]

I ran 2 400w over a 58 gallon for 3 years. No issue with heat but acclimation was difficult. Some corals went nuts with the growth others never seemed totally happy, but continued to grow. I tried a bunch of different lights and ended up liking the reeflux 12k and pheonix 14k the best. I am going with T5's on the next tank though based on the powerbill and acclimation issues.
-chris

 

[returnofsid]

I agree that this is too much lighting and WAY overkill. It will also cost you a lot more, in electricity, to run these bulbs, than if you were to run 250mh.

 

[travis_]

I agree that this is too much lighting and WAY overkill. It will also cost you a lot more, in electricity, to run these bulbs, than if you were to run 250mh.

So far my tank is doing very well with the 1000 watts of light and I am seeing the most polyp extension when both 400 watt lights are on. And as I stated before, I am only running my 2nd 400 watt light to simulate midday sun for 5 hours. Although, based on how good everything looks under the 1000 watts I may increase this. You all may say it is way overkill, but my corals are telling me something different as they are basking in the 1000 watts of light. And temperature control so far has been a total non-issue.

 

[Herefishyfishy]

Your coral is doing well in a bright tank, duh. Direct sunlight is much brighter yet, but I am not moving to Bali right yet. You own the lamps, might as well use them but if you get a chance to swap them, go for it. Once can easily spend $100-300 a month on electricity if you don't police it. Temp isn't a problem in the winter, it's in the summer.
Why waste the expence and create heat?


less is better. GO GREEN!