Optimal lighting solution for a 92g corner tank?

Pale Rider

Junior Poster
Dec 28, 2008
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Hi All,

After many years of keeping reef tanks I've decided to take a stab at a planted FW tank. I am planning to use my 92g corner tank (34" on each side, 24" deep and 48" across the bowed front) and was curious as to what would be the optimal lighting option for this tank. I'd like to use a HQI MH and can't really settle on a 150W or a 250W. I've poured over enough forum threads here there and everywhere to leave myself completely confused.=) It seems like there is a better variety of 150W bulbs that are readily available in the 5000-8000K range, but I know ADA makes a 8000K 250W if it turns out that that is not too much light. I do plan to have a pressurized CO2 system, don't know if that will be from the get go or not yet. If I'm completely off base wanting to use MH I'm open to other options. So with, what do you folks think?

Thanks,

Chris
 

Tom Barr

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Jan 23, 2005
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150 W is enough light.
You might conside a 150W + 2x65 W coralife pro hood.
Or a large bank, say 24w T5 X 8 or 60 and then only use a few at a time to get good even spread.

Even here, you should consider an open top design to be able to raise and lower the light, this will help make the light more even and better spread, and also give you a really good tool to adjust the light intensity to control the rates of growth(both plants- labor to prune, and algae if anything goes wrong).

As far as CO2, get CO2 gas system 1ST, then high light, never the reverse.

If you cannot justify or afford CO2, do not bother with high light!!!
This is a huge mistake many new folks make.
By then, algae is really hard to get rid of and 1/2 dead plants are hard to bring back. Go with a cheapo light for now, then when you have enough $, get the light.

Regards,
Tom Barr
 

Pale Rider

Junior Poster
Dec 28, 2008
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Thanks for the response. I had not considered the corallife hood, but that was because I wasn't smart enough to consider running it parallel to the radius of the tank.=) I do plan on the tank being open top and will go ahead and add the CO2 system from the beginning.

Thanks again,

Chris
 

Pale Rider

Junior Poster
Dec 28, 2008
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OK, so you got me thinking about T5's now. I could fit 8 of these easily enough above the tank. Do 8 of these equal the out put of the 150 HQI and 2 65 PCs? A straight up W to W comparison says no, but I think I have gathered from my reading that it is not an apple to apple comparison since they are differing technologies. I just want to make sure I will get a good spread of even lighting and good penetration in a 24" deep tank.

Thanks,

Chris
 

Gerryd

Plant Guru Team
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Sep 23, 2007
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Hi Chris,

Comparing lights at wpg is almost useless. PAR using a light meter is really the only valid comparison. You can get the Apogee for about $250 and are totally worth it. I bought one just so I can see what I had.

I think the T5 would be fine, but I have a 180 (72x24x24) and use 3x150 MH at 6500k about 14" above the surface and can grow anything I want.

Either fixture would do well I think. Remember that more light equals higher growth rates and nutrient demand and uptake......

Having the ability to raise/lower the lights as desired will help a lot as it is easy to reduce the light by raising the fixture.

Hope this helps.
 

VaughnH

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Jan 24, 2005
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192 watts of T5 light would be far too much if you plan to run all of the bulbs at one time. T5 fixtures, where each bulb has its own reflector are much more efficient at delivering light intensity than other types of lighting, so about 1/2 to 3/4 of that 192 watts should provide all of the light you will need. Tom's idea about using different groups of bulbs lighting the tank at various times during the day is to get light to the plants at different angles, avoiding shading of lower parts of the plants that occurs with a single bulb light. Having 8 of those bulbs on timers so only 4 to 6 of them were ever on at once, but each of them was on at some time during the day should work very well.
 

Pale Rider

Junior Poster
Dec 28, 2008
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Yeah, my thinking was to use the bank of 8 and then alternate the active lights through the day. The way I plan to hook it up I will be able to have anywhere from 2 to 8 bulbs, in multiples of 2, active at any given time. I've pretty much settled on the T5HO's now, if for no other reason than I've not used these before and I'd like to see how they work out. I have everything ordered (except for my CO2 system) and now just need to get to work finishing the stand so that I can start setting the tank up. Speaking of CO2, do any of y'all have any experince with the complete systems sold by Green Leaf Aquariums, or am I always going to be overpaying by purchasing a complete system from someone? I want a fully automatic system as I am a lazy person by nature and some things are just better left to computers.=)

Thanks,

Chris
 

Pale Rider

Junior Poster
Dec 28, 2008
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OK, so people don't have to repeat themselves I see several recommendations for the Sumo regulators so it sounds like a buying the piece parts is the way to go for quality components.

Thanks,

Chris
 

Tom Barr

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Jan 23, 2005
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Yes, you get a good product for the $ from them.

I'd suggest using only 1/2 those lights from the T5's at any one time. So the back 4 for 4-5 hours, the front 4 for the other 4-5 hours.

This gives a nice spread without the intensity or moving the hood.

You may also run the 4 back and the 4 front on/off opposite of one another every 30min, 60min, 2 hours, it does not have to be off for 5 hours one one side and then on for 5 hours on the others.

Up to you really there, just as long as all 8 are not on at once and you have about 10 hours of light duration total.

Regards,
Tom Barr
 

abcemorse

Prolific Poster
Sep 8, 2008
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I have 92 corner and am running the Coralife 192 CF light. Works well, fans a touch loud but not bad. I don't have much for high light plants, but I think I probably could if I wanted to. My only real issue is getting light to the back corner, but that's OK since that's where guts are anyway, I just put anubias on driftwood back there. Scaping is a bit tough, too, I'm still messing with different arrangements, getting close I think:rolleyes: . Sure make a nice piece for the living room, though, and doesn't eat too much space.
 

Pale Rider

Junior Poster
Dec 28, 2008
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Cool, I'd love to see a picture. I figured the back would be a bugger for lighting, but I have a nice driftwood stump I had planned on occupying most of the space back there. I've got an unoccupied space in my otherwise small living room and that's were I'm going to put the tank. I've kept reef tanks for probably the last 20+ years but the last hurricane (Galveston, TX area) wiped out everything because of the multi-week power outage. I'm hoping a planted tank will mange to last more than 3 days without power...ha But in the 3 days until I got back down there with a generator to try and save things everything had turned to slime and muck. Considering I'm within eye sight of the Gulf though and the water was within 10 feet of my house, the tanks were a small price to pay.=)

Chris
 

abcemorse

Prolific Poster
Sep 8, 2008
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Here's the tank, although this pic is a bit outdated, (October) I have since moved some stuff around and stuff has filled in, etc. I can get a more recent one up if you're interested.....you can see how dark it is in the back corner.

I have considered an additional fixture, I think Coralife makes 24" 96W CF that would fit behind the other one, but I want things to get balanced situated B4 I get more light.

92G_Cornerbow.jpg
 

Pale Rider

Junior Poster
Dec 28, 2008
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Looks good. I haven't figured out my exact configuration for the lighting yet, I think I may do a "T" shaped arrangement. My lights show up tomorrow so I can start playing around with that. I probably still lack a couple of weeks getting my stand ready, between work and everything else there's not a whole lot of time to dedicate to it at the moment, although I'm ready to get it going as soon as I get the time to set it up. I think I am going to try the "dry" method Tom talks about in a few of his posts. I'll see how that goes.=)

Thanks,

Chris