Lighting for a 90g

400watt MH would def be overkill. I currently use 2 150 mh with 4 t5 bulbs and seem to get pretty good results on my 9o. Although I am wanting to go all LED i am also considering going with a 6 bulb t5 setup

 

I dont really have any issues with light coverage actually. running a mainly sps tank here and have them on all lvls of my tank and nothing seems to be doing poorly.I do feel 250 watts would be better though. I think greenonion has 250 watt along with t5 on his 120 and last time I was over he said he hasnt ran his Halides all summer with no ill effects.

 

of course the AI ones are wonderful and have a great many features, you would need 2 though along with a controller and a way to hang them so roughly 1500 bucks. I have been doing some research on the reefbright leds also I think 4 would be needed and about 250 each for a 48 inch. you dont get the control you would with AI so its on or off but from my understanding they look amazing. Kylie you are a pretty handy gal though so perhaps a DIY setup would work for you. i think a 48 inch DIY led system wold run about 600 bucks.

 

Kylie, I'm going to be selling my 250w MH's shortly, I'm going to upgrade to T5 & Led combo.
They are Ice Cap 250w HQI, with custom made reflectors 12wide x 17long. I have two of them if you are interested, $200

 

Kylie,
I have done DYI for my biocube29 and getting ready to do a DYI for my 180g I am going to be building in to my wall of my basement in the near future.  LEDs are nice but it depends if you are going to be doing SPS corals or not.  A lot of people say for SPS corals you should use Cree XP- LEDS vs. the Cree XR leds.  I have some SPS corals in my biocube and they are doing well.  The other thing you need to consider is if you want dimmable for siumulating sunrise and sunset.  The differnece in price is usually around 10 dollars more per driver for dimmable for a rough estimate.  Mine on my biocube are dimmable i have 24 leds 2 drivers one for white one for blue and spent a little over 200 for them then wired everything myself and let my apex dim them.  I didn't use lenses because my leds are very close to the water anyway, for your setup you would probably want 60 or 40 degree lenses to get enough light 2 feet down at the bottom.  60's should do it i think.  A lot of kits out there come with the lenses.  I would think the 48 led dimmable kit from rapid LED for $385 would be plenty for your 90gallon tank but I will do a bit more research first and make sure and let you know if that is something you are interested in.  You would have to buy a heat sink for them which shouldn't run much more then 50 bucks.  I only run my biocube at about 75% power and on top of that I have the drivers dialed way back too so really I am only running 75% of about 75% power if that makes sense.  Also need to consider if you want moonlight but those are pretty cheap too.  My 24 leds are supposed to be the equiv to 175 mh but I can't say for sure other then they are really freakin bright /DesktopModules/ActiveForums/themes/_default/emoticons/smile.gif If your interested in LEDs and want to see some if your near Cedar Rapids more then welcome to check out my biocube anytime and see what they look like to help you decide if LED is a direction you want to go.  Thats my .02 if anyone else familiar with LEDS wants to chime in feel free I am still a bit new to LEDs so another opinion is always welcome.
J

 

I'm going to retro fit 5 10w LEDs to a single 48" heat sink to give the shimmer effect that I like, and let the T5s do the brunt of the work as far as growth is concerned. I will try to get a short video latter today of a single 10w blue LED.

 

Nice meeting you for lunch today kylie, hope I answered many of your questions and feel free to contact me anytime on future ones. 
J

 

Wow created a monster /DesktopModules/ActiveForums/themes/_default/emoticons/smile.gif  LOL aren't LEDs cool?  Ok on to the questions.....
[class="Apple-style-span"]#1. You mentioned that certain drivers would possibly be able to handle 18 leds in series. Do you know which ones that would be? And could you direct me to the dimmer switch you were talking about? [/class]
Here is the link to one of the drivers, http://www.rapidled.com/servlet/the...ant/Detail  There are some more I'll look them up and let you know on those.Here is the little knob dimmer I was telling you about if you want to skimp by till you got a controller. http://www.rapidled.com/servlet/the...ter/DetailHere is another option with a little more programmable options for you in the mid term.  http://www.rapidled.com/servlet/the...ler/Detail
[class="Apple-style-span"]#2 And is this the "light" controller you were talking about? #2.5 Did this need a different thing connected to it in order to gradually turn on and off my lights?[/class]
That is part of it.  You would need that as well as this. http://www.neptunesys.com/index.php...&Itemid=40
[class="Apple-style-span"]#3 If I couldn't afford this yet, could I still get the LED's and have them running on an outlet timer?[/class]
Yes you can just have the LEDs on an outlet timer, but you have to have the dimmers hooked up to something or the LEDs wont turn on but you could use that 3.50 cent dial dimmer to do that just fine.
[class="Apple-style-span"]#4 So is this saying, that should I go with the 18 white, 18 blue (if thats indeed what crabbyo has), then I could use 2 drivers. Each driver would have one set of 9 LED's linked in series, which is linked parallel to a second set of 9 LED's? (making 18 LED's total connected to 1 driver). That wouldn't be so hard to do. [/class]
I have not explored this much myself, I'll do some reading and get back to you in the next couple of days on this one.  /div>
[class="Apple-style-span"]#5, 6, 7. You mentioned if I got the pre-drilled heat sink, then I would be able to rearrange my LED's once I upgraded to the 90g. Can you rewire LED's? Once they are connected, can you take them apart again and rewire them? Or does that damage the LED? [/class]
The short answer is Yes with care.  The long answer is like I said at lunch if you plan on moving them and using the predrilled, make sure sure sure you just get thermal transfer paste and not thermal transfer apoxy.  If you get the glue/apoxy they cannot be moved because that stuff hangs on like none other and you will break the led before you break the bond.  You still should use thermal transfer paste between the led and the heat sink even with pre-drilled even if you plan on never moving them.  The wiring can be redone if your very careful and have a good soldering iron.  Long as your careful and don't have too much solder on the LED you won't damage them moving them once or twice, but you would not want to make this a monthly thing, and like you said you only planned on maybe moving them once at most.
Again I am no expert, so anyone if I am off the mark on anything please chime up I do not want to be giving bad info here or if there is a better way by all means I am willing to listen LEDs are so customize-able there is so many ways to do things I know a few on this board have a bit more knowledge then me might be able to help with a trick or two of their own.
Have fun and don't be afraid to ask any more questions you still have 3 left in your quota before I cut you off /DesktopModules/ActiveForums/themes/_default/emoticons/smile.gif  Just joking ask ask ask ask away.
J