Lighting Question

[SB0169]

Once again I need to tap into the wealth of information that is so prevalent on this forum. For the past few months(since I inherited my setup and became hopelessly addicted to this hobby) I have been running a PC fixture with 1-96w 10000k daylight and 1-96w actinic on my 46 bow. That is until today when I plopped a 175w MH with 2-65w actinic PC and 4 LED lunars on it. Actually I hung the fixture from the ceiling about 6 inches above water level. So now I have about 309 watts total, or about 7w/gal. compared to 192 total watts or 4w/gal. Why is it then that the PC,s seemed to provide so much more light? They definately lit it up more than my new (slightly used) fixture. I hope I didn't make a bad choice and waste my money. Thanks for any input.

 

[ronj]

that is really odd!! the halide should definitely brighten it up... what color bulb are you using?? also, is there a dimmer switch on the ballast?? how old is the 175w bulb???

 

[SB0169]

It's a 14k bulb, The bulb is 6-8 months old, and I don't see a dimmer switch...

 

[dailydriven911]

Can you post a pic of your setup?

 

[SB0169]

Can you post a pic of your setup?

I'll post a pic when I get home this afternoon.

 

[ronj]

maybe you should try a 10k bulb...my 10k's light my tank alot more than my 14k's did!!

 

[SB0169]

maybe you should try a 10k bulb...my 10k's light my tank alot more than my 14k's did!!

I may try that. Is there a way to change the ballast to a 250 watt? The ballast is in a separate control unit. I wouldn't mind having more wattage.

 

[roscoe]

How wide is your 46bow front? Metal halides generally will only cover a 2x2 sq. ft area unless you use a lumenarc reflector which can cover a 3x3 sq. ft. area so you will have dark spots on both end of your tank.

 

[SB0169]

How wide is your 46bow front? Metal halides generally will only cover a 2x2 sq. ft area unless you use a lumenarc reflector which can cover a 3x3 sq. ft. area so you will have dark spots on both end of your tank.

My tank is 36 wide, so it is definitely more dim on the sides, but even the center is not as bright as I would like. What is a lumenarc reflector, and where can I get one?

 

[roscoe]

Lumenarcs are one of the best reflectors out there. Just do a google search and you will find them. There are the minis also which is what I use over my 40b.

 

[ronj]

a lumenarc-mini would probably be best for that tank

 

[trido]

Alot of 14k are way dimmer than 10s

You went from a 96W 10k PC to a 175W 14k MH.
And then went from a 96W actinic to 130W actinic

40 watts more actinic isnt really going to make things bighter, and the difference in your MH is probably going to look more like a 30 watt boost to the naked eye due to the Kelvin difference. Im not suprised that your dissapointed. MH has better depth penetration than PC and I'd bet you corals can feel the difference. If you switch that bulb out to a 10K you will most likely feel like you were hoping....Like money well spent.

Two days ago I switched my tank from 10Ks back to 14Ks. My tank is probably 25% dimmer.

 

[ronj]

make sure you don't burn your corals up if you have any.. the light may not look brighter, but they are definitely getting alot more light..

 

[SB0169]

I have some leathers and mushrooms. No SPS. So far, they seem to enjoy the light. Ron, Isn,t 500 watts of MH too much for 40gals?

Trido, I'll try a 10k. Thanks a bunch for the info. Who is your preferred supplier? I was thinking Marine Depot? Or is there a better place?

 

[SB0169]

Update

So after further examination, the sticker on the fixture says 175w, 20000k. Problem is, it is a double ended bulb. I can't seem to find 175w double ended... What's up with that??? How do I know what it really is? are the bulbs themselves marked?

 

[Bainic]

Not that i'm an expert but I think that 6 inches is a little bit too close, I wouldn't put halides any closer than 9 inches myself.

 

[trido]

Can you ask the seller if they are the stock bulbs? How old is slightly used?
After a quick search I came up with this DE bulb. This Ushio aqualight is supposed to have the same par output as some 250 bulbs

 

[SB0169]

He said they are all stock bulbs. About 6-8 months old. The auction you showed me is for a 250... there are also no double-ended 175's available from him. Makes me wonder if it is a 150 or a 250???

 

[trido]

The auction you showed me is for a 250

LOL they tricked me. I googled 175watt DE MH. and actually thought I saw one.

Id look into contacing the manufacture or find the part number on the ballast and google it. You'll come up with the anwers you need if you look hard enough. If it is a 20K bulb its getting about time to replace it anyway.

 

[SB0169]

LOL they tricked me. I googled 175watt DE MH. and actually thought I saw one.

Id look into contacing the manufacture or find the part number on the ballast and google it. You'll come up with the anwers you need if you look hard enough. If it is a 20K bulb its getting about time to replace it anyway.

I will take the case apart on the controll box and check the ballast tomorrow. Thanks a ton for your help!