MH Lighting

[bhammer]

All, if I go with a 500 watt MH light and use 14,000K bulbs, do I need to supplement with any other bulbs, like the actinic for my LPS and SPS and in the future, clams.

My 115g tank is about 20" deep at the deepest point before sand.

thanks....

 

[thominil]

TOO MUCH LIGHT! Are you trying to bake your fish? Just go with a 150w or a 250w and that should do it. Rarely do tanks need over 250w. Actinics are eyecandy and not required IMO. 150w should be fine though.

 

[bhammer]

Okay, but now I am confused. One 250w would be less than the 6X54 T5 I have now. The LFs said I could do many corals but that clams wouldn't do well. What am I missing here?

He said that a 2X250 MH would be nice and then proceeded to tell me to look online as his are too expensive. It's not like he was trying to sell me lights.

 

[InfernoST]

I believe thominil thought you were talking about a single 500 watt lamp (if I go with a 500 watt MH light and use 14,000K bulbs) and your tank would require 2 lamps so that would be 1000 watts in a 20 inch deep tank, he's absolutely right if that were the case (115 gal of Fish Broth). 2 250's will give you a lot of light @ 20", I have a 120 60 x 18 x 26 with 2 250's & 4 T5HO's which is plenty of light. The actual tank dimensions would be a great help.

 

[ccCapt]

20" is pretty shallow. You can definitely get by with 175w MH's. How long is the tank? Depending on the reflectors you use and the length of the tank, 2 x 175w should work fine.

On a side note, don't think just because a bulb is a 250w MH it's more powerful than a 175w MH. In metal halide lighting, the output of different manufacturers bulbs vary greatly. For example, a 175w Iwasaki 15k MH bulb puts out almost 2x the PAR as some 250w bulbs.
Here is the ultimate site for MH bulb comparisons.
Manhattan Reefs - Sanjay's Lighting Guide

 

[neilanh]

bhammer, I think everyone is poking at a single 500W bulb here. There's several factors to look at. Plus, I'm not even aware that there is a 500W system out there. I know about 400W, and I know about 1000W, but never heard of a 500, but that could be just me.

500W is probably a good choice for your tank, IMO. However, MH bulbs only put out so much of a footprint, so in order to cover your tank you'll probably want to split it between 2 bulbs, meaning you have 2 250W bulbs to create the 500W of total light you're after. Like Larry said, 175s could work as well depending on your bulb choice.

As for needing supplements, I think that's really personal preference. Bluer (higher K) MH bulbs have the blue color spectrums within them, so it's not necessary to have any supplementation, just many people prefer to have it as well so they can create a dusk-to-dawn effect by having the actinics on first for a little while, then the MH, then reverse the order when shutting down for the day.

 

[bhammer]

Sorry guys, I wasn't exactly clear. Yes, I am talking about a 2X250 and not a single 500w assembly. The tank is a flat hexagon and the internals, without sand is
Back - 50 1/2
Front - 41
Total width - 21.5
Flat side - 16
Slant side - 7
Depth - 25

I was looking hard at the Current USA SunPod PowerPaq HQI Lamp & Lunar Lights but really like the Outer Orbit Combo units.

becasue of the hexagon, it is difficult to put light fixtures up unless I hang them both. Don't know if the wife would go for hanging lights though.

What lights / setup / wattage would you go with? If not the ones I listed, what do you like?

 

[thominil]

The HQI/T5/lunar unit is a nice fixture from what I have seen. I was planning on getting it for a 150 I was going to get before petsmart sold the 150....May just end up finding another 150 and getting that fixture. Just a little pricy lol. May sure you have the wattage to support that beast though, sucks up 6.2amps and don't forget about the other equipment that will be running too.

 

[bhammer]

Darn, I am having a hard time finding the T5/MH combo unit online... I will have to continue looking. Most places show them as disconinued? Spoke to marinedepot and they said they were as well...

Yup, the draw on these things is a bunch. I'll have to double check but think I still have about 3.6 amps / 432 watts to spare. Have to make sure I plug any other outlets on that breaker.

I am also looking at doing two units as a backup:
48 inch Current USA SunPod 2x250W 14K HQI-MH w/ 18 Lunar Lights
48 inch Current USA Nova Extreme 4x54W T5HO

I may even go down to a 2 bulb fixture as this setup may be about 1/2 too big. I just can't make up my mind.


Same amount of light, but at a much cheaper price.

 

[thincat]

I had to add two additional dedicated lines for my reef setup. Better safe then sorry. I only needed one additional line but the same effort to run two. Now I wished I had run three.

 

[bhammer]

I had to add two additional dedicated lines for my reef setup. Better safe then sorry. I only needed one additional line but the same effort to run two. Now I wished I had run three.

I had thought about that. I'd have to go up two stories and then back down two. Or, since the room with the tank is in, is along the garage wall, I could just run conduit up, over and back down.

 

[thincat]

Why do you have to run it both ways? I used romex cable, I ran 12/2 w/ground copper wire w/ a 20a breaker.

 

[thominil]

Check with aquacave, they have it.

 

[bhammer]

Why do you have to run it both ways? I used romex cable, I ran 12/2 w/ground copper wire w/ a 20a breaker.

I don't have to run it both ways. I was saying one or the other. If I run the conduit, it will be on the outside of the garage wall and would be the easiest way to do it. It's about impracticle to run it in the walls.

Check with aquacave, they have it.

Yup, found it there and ordered it last night. Grand Total: $1,049.97; ouch!!!

 

[thincat]

Do you have double walls? Do you have an attic? They also sell romex trim in lumber form to cover the cable and you just paint it to match the house color or trim color.

 

[InfernoST]

If your going to run Romex you should use 12/3 with a ground this way you will have an additional spare circuit in case you need it. By code two hot legs can share 1 neutral.

 

[bhammer]

If your going to run Romex you should use 12/3 with a ground this way you will have an additional spare circuit in case you need it. By code two hot legs can share 1 neutral.

Yes, this would work but the 12/3 wire would not run two GFCI. I don't think you can run two circuits with GFCI on two hots and one neutral. I think I will end up running 2 12/2 so I can have two 20 amp circuits, both with GFCI. I will have to check into a two pole breaker; this may be the way to do it.

 

[InfernoST]

If you used GFCI outlets the instead of the breakers it would work with the 12/3, otherwise then yes you would have to run 2 separate home runs back to the panel. My bad I didn't realize you were planning on using GFCI breakers. With GFCI outlets you can only have one on each circuit but every outlet connected to the load side of each GFCI is protected by that GFCI.

 

[bhammer]

No "my bad" needed. I am still in the thinking / planning phase of this. I went and looked at my load panel and it is full up anyways. Darn home builders, not leaving any extra room in there. Guess to do this now, I will have to add a second load panel. Something I have not done before but it's as good of time as any to read up on it. Will just have to figure out how to kill the incomming 240. Think I will have to do that at the meter panel.

 

[spoonman]

Not to hijack but, have you guys that have MH seen a huge jump in your electric bill? About how much?