How much light i need over 70g cube??

Trigs · #1 09-04-2008, 11:04 PM

Wondering how much lighting i need over a 70 gallon cube, 30Lengthx 30W x 18Height i currently have a 250w mh hqi that i would be putting on and centering it for the middle but i dont know how much coverage it exactly gives, anyone have any experience with this?

Myka · #2 09-05-2008, 01:51 AM

In order to cover the 30x30" footprint you need yo use a Lumenarc or Lumenmax reflector with a SE or it will be much dimmer at the edges of the tank. "Traditional" reflectors don't have the ability to spread the light that far. If you want it for SPS, then I would suggest overdriving the SE bulb with an HQI ballast. If you don't mind it being dim on the edges, then your 250w DE bulb should do the trick, you'll just have to either have just sand along the edges or have lower light corals. Is your current ballast an electronic or an HQI?

Marlin65 · #3 09-05-2008, 04:22 AM

250w HQI in the center with two T5s on each side of it one daylight one actinic in a custom built canopy by you.

You can put the white T5s on the outside to get the spread.

Trigs · #4 09-05-2008, 05:29 AM

well i have a hqi ballast and bulb in right now, so i mean i think it should work? but i could be wrong and ya the t5's on the edges should be a nice fill in

Myka · #5 09-05-2008, 05:42 AM

They won't fill as well as you'd think they would. The average MH bulb will cover a spread of 24x24". T5s will be 24", they aren't going to cover the length of the tank any better! Even if you stagger them...you'd end up screwing around a whole lot, plus you need to squish some T5s in there for actinics anyway. The cost of a set of retro fits to put more white lights in would be about $75 less than replacing your DE with an SE socket, and changing to a Lumenarc fixture. You'll get hella more par running a SE bulb off that HQI ballast. You could always just stick with what you have for now, and if you decide you don't like it, then just upgrade to the SE socket, and buy a Lumenarc. You will need some actinics though...looks waaaaay better.

Trigs · #6 09-05-2008, 05:45 AM

yah for sure actually i agree wth you, and the ballast is hqi i have checked and made sure, so you suggest changing the bulb eh? or buying a different tank haha

Myka · #7 09-05-2008, 05:52 AM

Quote:

Originally Posted by Trigs

yah for sure actually i agree wth you, and the ballast is hqi i have checked and made sure, so you suggest changing the bulb eh? or buying a different tank haha

Well you either match your light to the tank, or you match the tank to your light!!

A perfect match for your light would be a 24x24x? cube, preferrably about 16-18" deep. That would be the "perfect" tank for your light. Honestly, your light wouldn't be bad over a 30x30" tank, it just wouldn't be ideal. In fact, if you just wanted an LPS tank, not an SPS tank I would say your light would be quite ideal over that 30x30" cube, albeit I've never been a fan of DE bulbs.

Your current 29g tank is 30x13x19" (if I remember right) lit by a 250w DE bulb, so putting that same bulb over a 30x30x18" really isn't getting you any further ahead now is it?

Trigs · #8 09-05-2008, 05:54 AM

yah true that no i agree i agree ill work on it, looking for a tank first dont know where to find one, how much you think it worth brand new reef ready? a 24x24 or a 30x30?

Myka · #9 09-05-2008, 05:57 AM

I edited my above post while you were replying (I'm bad for that), so please re-read it.

You'll have to get custom if you want Reef Ready. Otherwise you'll have to do the overflows yourself, or buy a used one with them installed already. If you have patience you should be able to find one in the next 6 weeks or so. They're always popping up. When I was pricing out cubes I think Seastar made a 30x30x18" for $300ish...? But I'm pretty sure that is a "custom" size.

Trigs · #10 09-05-2008, 05:59 AM

yah that sounds more custom than anything, and i re read the post agreed with that, how many gallons is a 30x30 n 24x24?