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I personally would not want to try and handle a 6' or 8' T5 bulb.

And remember the WPG rule breaks down on larger tanks. 2 wpg is a lot of light on a tank that size.

Personally I would go with AH Supply 55 watt kits mounted front to back. It gives you lots of lighting options because you can start with say two bulbs coming on, then move up to four and so on. Kind of simulate a sunrise and sunset effect in the tank. Also a lot more choices in bulbs.
 

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Discussion Starter · #4 ·
What i meant by 6 and 8 is the bulb amount. not the length, sorry for the confusion. still sticking with 4ft fixtures but instead of 4 bulbs per unit. 6 or 8 bulbs.

thanks for the replies and links guys!


joe
 

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T5 HO bulbs don't come in lengths longer than 5 feet. If you're set on T5, you're looking at a load of 4 footers.

In my experience, mounting and wiring up that many flourescents is a serious PITA. If it were my tank, I'd look at buying two of these and calling it good. A similarly equipped retrofit kit won't save you much anyway.

That being said, do you have your heart set on T5? For a 24" deep tank, I think metal halide is a much better choice.
 

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Discussion Starter · #6 ·
T5 HO bulbs don't come in lengths longer than 5 feet. If you're set on T5, you're looking at a load of 4 footers.

In my experience, mounting and wiring up that many flourescents is a serious PITA. If it were my tank, I'd look at buying two of these and calling it good. A similarly equipped retrofit kit won't save you much anyway.

That being said, do you have your heart set on T5? For a 24" deep tank, I think metal halide is a much better choice.
I was checking those out. trying to keep costs down if possible which i know cant always be. yes i have thought of MH's but i want to keep my Elec lower then what MH's would do. if i buy MH's i would be forced into just doing a Reef and not going planted, so yes in all honesty i would like to stick with T5's

if i went with that setup from reefgeek, that would give me 864 watts for 240gallons would that suffice?
 

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I was checking those out. trying to keep costs down if possible which i know cant always be. yes i have thought of MH's but i want to keep my Elec lower then what MH's would do. if i buy MH's i would be forced into just doing a Reef and not going planted, so yes in all honesty i would like to stick with T5's
IMO, (4) 175 watt 6500k metal halides (700 watts, for those counting) in good reflectors would outperform 864 watts of T5 lighting hands down. Even a set of cheap bulbs in Lumenarc III reflectors would make the T5 hoods look like night lights. Watt for watt, metal halide is significantly more efficient than flourescent. More expensive startup costs usually, but you get more usable light with less energy usage.





if i went with that setup from reefgeek, that would give me 864 watts for 240gallons would that suffice?
That would be considered high light. Someone will invariably chime in and call it overkill, but it takes a lot of "punch" to get light to the bottom of a 24" tank (another reason MH would be preferable). You could go with 6 bulb fixtures, but the 8's are only marginally more expensive and would make a noticable difference. Regardless, it would be enough to grow just about anything. I hope you have your pressurized CO2 and ferts on standby.
 

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That would be considered high light. Someone will invariably chime in and call it overkill, but it takes a lot of "punch" to get light to the bottom of a 24" tank (another reason MH would be preferable). You could go with 6 bulb fixtures, but the 8's are only marginally more expensive and would make a noticable difference. Regardless, it would be enough to grow just about anything. I hope you have your pressurized CO2 and ferts on standby.
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Bull****, bull****, bull****.

A standard 55 gallon tank is 21' deep. But we NEVER hear people talking about how hard they are to light. I have AH Supply kits over a 55 and I can grow anything I want. People have them over 90 gallon tanks (24" deep also) and can grow anything they want.

This crap has to end. And it has to end soon. I don't even consider a tank "deep" unless it hits the 30" mark.

Joefish:

You must have missed my post telling you that you only need 2 wpg on a tank that size. An any decent lights with decent reflectors will "punch" the light though the 20"-21" of water you will have.
 

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Hahah. 864 watts over 240 gallons. That's WAYY plenty.

I'd aim for ~480 watts over 240 gallons.


Wuss. :tongue: Although before I say more or you say less, I guess we need to know what he plans on growing. I assume he wants those demanding almost neon colored ground covers like all good planted aquarists.


Halides for the win!
 

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Bull****, bull****, bull****.

A standard 55 gallon tank is 21' deep. But we NEVER hear people talking about how hard they are to light. I have AH Supply kits over a 55 and I can grow anything I want. People have them over 90 gallon tanks (24" deep also) and can grow anything they want.
How is it bull****? We're posting opinions here, not absolutes. I prefer high light and I outlined a few reasons why I feel the way I do. I speculate that you don't hear much about 55 gallon tanks because they're aren't a lot of serious aquarists out there doing fully blown, high tech 55's (or any standard size, for that matter). Aquascaping is an issue. How many cutting edge tanks even exist in the US today? This hobby is in its infancy.

And yes, it's quite possible to grow most, if not all plants with 2wpg, but you can't argue that the growth is slower and very different. There is a big difference between maintaining a plant at 2wpg and blasting it with 5wpg. I much prefer the latter.

Why is it that Amano, Knott, and other guys who's living depends on their tanks all seem to have switched to MH? Granted, I don't put a lot of stock into it, but the ADA obsession around here shows that a lot of people do.




This crap has to end. And it has to end soon. I don't even consider a tank "deep" unless it hits the 30" mark.
Don't be a bully. I consider a tank deep at 24". You say 30". Light penetration into a water column isn't linear. As a tank gets deeper, it becomes exponentially more difficult for light to reach the bottom (which is where the most light demanding plants usually are). In general, metal halides are much more efficient at water column penetration.

For some interesting reading on lighting, I'd encourage everyone to check out Sanjay's Page. It's geared towards reefs, but a lot of the general information still applies.
 

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I will bet that the most common large size planted tank is the 55. Just because they are most available and relatively inexpensive.

I know all about light and water. And three inches doesn't mean squat. The inverse square law is based on FEET of water, not inches.

I'm not being a bully. People see the term 20H (which is just under 17" high) and start telling people they need more light because of the tall tank. One moron even told someone they would need 40% more light due to the depth of the tank. A 24" tall tank with 3" of substrate is only 21" of water. So do you consider that in your definition of deep?

The research has been done on the drop off of light intensity in fresh water tanks. As I recall it's less than 2% per inch. So a couple of inches doesn't mean squat unless you are at the extremely low end of the power scale.
 

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Discussion Starter · #14 ·
That is a Beautiful tank!

i didn't mean to start a war over lighting here i am just a newb to when it comes to doing it the right way with live plants and just want to do it right but at the same time save me some $ being a father allot of my $ go's to my son. i am by all means not saying that i want to pinch every penny, but i think you guys know what i mean.

If T5's will do the job then i just don't see any justification in going with MH's .

not sure if i said this but this tank is sitting in my living room. and by no means can i have screaming Mh's blaring out everyone that sits in it. as where i can hide the T5's in the canopy without having to add fans and worry about my tank water warming it.

i have 2 canopies. 1 slim that i use reg fluorescent in and have used PC's but it did get warm and my second one is taller i made myself so i can hang T5's and get a little more room for cooling purposes.

here are the pics.

taller canopy




slim canopy.





As for what type of plants i want, yes i want the bottom covered in "Green" but who doesn't? well maybe someone, but i love the look. then after that just a variety of plants. not really sure with what yet.
 

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Joefish,

FWIW, I would go with the T-5s. MHs would heat your tank(not to mention the room the tank is in) and do cost alot more to run then T5s. I do disagree with Rex however that 2wpg would be enough. I dont think just because your tank is big that rule breaks down.

If you take Rex's Example above about a 55g tank being 21 inches, and your tank being 24 inches tall, then how possibly is that different on the wpg rules? The light is still penetrating through depth of water, not volume of water. I would aim for 3wpg and co2 and call it a day...I would do either the 6 bulb or 8 bulb(which ever you can do) and feel good about a good descision. T5s are cheaper to run the MHs, and cheaper to replace bulbs..
 

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I will bet that the most common large size planted tank is the 55. Just because they are most available and relatively inexpensive.

I know all about light and water. And three inches doesn't mean squat. The inverse square law is based on FEET of water, not inches.


This doesn't jive with my experience or research.

Dana Riddle said:
Of course these measurements fall off as we go deeper in the tank. That needs to be kept in mind when placing corals since at lower levels the PAR that started off at 1000 mE's, may only be 100 or 200.
He's referring to a 24" deep aquarium. Source. Here's an anecdotal experiment done in a 21" deep tank. In every instance, PAR dropped a lot more than 2%/inch.




I'm not being a bully. People see the term 20H (which is just under 17" high) and start telling people they need more light because of the tall tank. One moron even told someone they would need 40% more light due to the depth of the tank. A 24" tall tank with 3" of substrate is only 21" of water. So do you consider that in your definition of deep?
I'm not telling anyone they need as much light as I like to have. I consider the substrate depth just as you would with an 18" tank having 3" less for light to travel.

I think we are missing each other on need vs. want. Years ago, my 20H had 2x55 watts of PC lighting (back before they really caught on for planted tanks), and I caught all kinds of crap from the "overkill" bandwagon. I specifically recall you blasting me on the old AB board haha. Point is, I grew riccia by the pound and was able to grow a short, thick lawn of this new, exotic foreground plant called glossostigma. I put some in my other 20h with 1 55 watt pc and it looked totally different (and not to my liking). I haven't had less than 4wpg since. I set up my new tank primarily to grow a field of HC and put a ton of light on it. It's just a preference.
 

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I have seen many studies on the depth of water, they dont all jive either. One I have refered too in the past is from Sanjay Joshi. Take a look here: Advanced Aquarist's Online Magazine - Feature Article: Underwater Light Field and its Comparison to Metal Halide Lighting but here is a quote from that article:

Most of the SPS and other corals in our reefs are found in waters less than 15-20 meters deep, but our reef aquariums are usually only 24 to 30 inches deep. At this depth of water, the amount of light lost to absorption by the water is quite small. Using the diffuse coefficients for the ocean waters presented above, the amount of light at 700nm absorbed by 2ft of water is 33% of light just below the surface. For light at 400nm this is only 4%.
Also here is a graph from that article comparing light from a MH at a depth of 24" vs surface



Keep in mind that is between SURFACE vs 24", if your comparing it to say 21" the difference will be much less, even though it doesnt appear to be much anyhow.

It is commonly agreed that WPG rule breaks down on small tank (they need more WPG) and large tanks (need less WPG). Of course thats all relative to your needs to begin with (co2, light requirement of plants). And for deep tanks, good reflectors help dimish loss due to inverse square law. If the reflectors direct most all light straight down, the only loss will be what is absorbed by the water. And with flourescent lighting the inverse square law is actually more like an inverse 'double' law, seing how they are line sources of light and not point sources.

I am setting up a 240G also. I have looked at several options including MH, MH+T5, T5HO, T5ODHO, and CF. Many have regarded T5HO as being as effecient as MH when used with good reflectors, even more so since some MH brands are not that good. But the cheapest route is AHsupply, 10 x 55W, giving 2.3WPG. Thats $310. Now add in the bulbs, assuming half from ahsupply at $19ea and half GE 9,325K at $14ea yields a total $476. I am really thinking about going that route, and like Rex says you can mount the light front to back.
 

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Tom Barr has grown Glosso at 2 wpg in most every tank size.

The WPG rule does break down on large and small tanks. It has to do with intensity. Once you reach the light intensity that a plant needs to survive you don't need extra. And the plant doesn't care about how much water it's in.
 
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