Lighting for 20g long tank

[DUSTIN323]

I am turning my 10g into a 20g long tank I already have flourite in the 10g that I was going to switch over and have a Hagen c02 system I don't know what kind of lighting to get. I want my plants to actually live this time unlike in the 10g but I realize that my problem there was I was using indacasent lighting I was looking in a drsfostersmith catalog and saw I could get a dual flourescent strip light that would be 40 watts (2 watts per gallon) or for about 20bucks more I could get a compact flourescent light that is 55 watts (2.75 watts per gallon) I will get plants that don't require high lighting more like low-moderate lighting so what would ya'll get because I've never had sucess with plants but then again I've never done the right research.

[Damon]

N.O. flourescent is good and works just fine. T5 is a better option as it is more efficient and will give a better spread (No dark corners). Either way is great; though I don't see how you can get the fixture for under $40.00.

Here are some choices...........
http://www.bigalsonline.com/catalog/...d1=1843;pcid2=

This would be my choice here...............
http://www.bigalsonline.com/catalog/...tegory_id=2259

or.........
http://www.bigalsonline.com/catalog/...d1=1843;pcid2=

[DUSTIN323]

I like the compact flourescent you posted but do I really need that many watts I saw the pics of your 20 gallon "healer" tanks and I like it and the plants are beautiful did you use T-5 in that one? I just wanna make the right choice the first time and like I said I just want easy plants that require low-moderate lighting. I guess I am concerned about the wattage because I've heard alot about watts per gallon

[Damon]

If you want a lower light tank, go with the T5. Better spread. WPG is a rule of thumb comparable to 1 inch of fish per gallon of water. Its a very vague idea only suited for the basic of fishkeeping. The same applies to wpg. Lumens are more important as the wattage really only applies to the amount of energy the bulb uses.

[shev]

Well jebo is pretty cheap. but for a reason, their ballasts apparently burn up bulbs faster. but cf 55 or 65 watt bulbs on ebay are cheap. 24 inch 110 watts CF for $35 plus $16 shipping comes with a 55w 10000k bulb which I like, and an actinic one which wont help much. or a $25 plus $15 shipping 24 inch 65 watt jebo fixture, uses 1 65 watt cf straight pin bulb, external ballast but it comes with a 50/50 bulb.

coralife 30 inch 65 watt pc light. starting bid $5

on ebay you can get 55 or 65 watt bulbs 10k for 10$ each, or 6400k (kind of yellow, but much cheapers) $6 each. 55W and 65W bulbs are interchangable since the wattage to the lamps will be driven by the ballast.

[shev]

I think I have to disagree with simpte. the watts matter, lumens dont for a planted tank. lumens just measure how bright the bulb is to the human eye. the human eye is more sensitive to the green parts of the spectrum, making it seem brighter to us. but plants reflect the green part because they are green, and they use the red and blue parts of the spectrum. so even though it may appear brighter to us with more lumens it will be dimmer to the plants.

[Damon]

Why watts per gallon don't matter.
http://www.rexgrigg.com/mlt.htm

Or to simplify it, put a 55 watt incandescent bulb over a 20 gallon tank and see what happens.

[shev]

oooh I see. that does make sense.

but watts and lux are related. a lux is equal to a certain number of milliwatts, at a certain frequency. so a 55 watt bulb with a green kelvin rating will hold more lumens, which means more lux, than a 55w bulb of the blue and red region, even though it may not benefit the plant more.

[DUSTIN323]

Yeah I thought its kind of about both because in my ten gallon I had more than 1 watt per gallon low light plants and they didn't do good because I had indacascent

[DUSTIN323]

I think I'll probally go with the T-5 because I do want a lower light tank and it's a few dollars cheaper than compact flourescent and I trust your word simpte from seeing your 20g healer tank. I probally would go with the compact flourescent since I didn't know about lumens. So thanks shev and simpte

[DavidDoyle]

I have a nice planted 20L. It uses the twin 20w strip to which you refer above. To use that fixture you need to get the glass top designed specifically for a twin tube strip. This fixture will leave the 3 inches at either end of the tank w/o light directly over them.

If you are going with low-med light plants, this would be my choice.

One of the facotrs many folks dont take into account in lighting a tank is dispersion. As lidght radiates out from a source two things happen: The intensity weakens and the area of illumination increases. This is why the wpg is only a rule of thumb. In a shoower tank like a 20L the light will reach the bottom of the tank before is has a chance to disperse very much. For this reason it take more watts to get full coverage at any given light level. On the other hand a taller tank has great dispersion since the light has the distance down to spread out before reachig bottom. So you can actually use less watts to achieve a desired light level. this is only true up to a point as the distance soon becomes a limiting factor beyond a certain depth.

The biggest problem with power compacts over a shallow tank is that the area of the tank directly below the bulb(s) will get very intense light which means either super growth if a tank is in balance or algae if it isnt. However, other areas of the tank will get much less light.

Plant selection for a 20L is important as anything tall growing really wont work- it takes over too fast. I have water sprite, java fern, anubias, a few crypts, 3 compacta swords, frogbit and african fern in my 20L and every week do major pruning and removal. I use Excel but no added co2.

[DUSTIN323]

Ok well I was probally going against the power compact so you're saying that power compact isn't the way to go dual standard or T-5 would be best for me?

[MyraVan]

I think I'd agree with everyone else, that the dual strip, for 40W in total, would be the way to go. With the higher wattage lighting, you'd have to be more careful to get everything balanced (amount of light, ferts, etc) else you'll end up with a big algae bloom. (Plants need to have everything in the right balance to grow properly. For example, if you have too much light, in comparison to other stuff, the plants won't be able to make use of it, but the algae will.)

You don't need CO2 to have plants grow successfully, at least with the amount of light you're planning to use (40W). With the higher wattage of light of the CF, it's more likely that you would need CO2 to avoid algae.

Make sure that you add more Flourite; the amount you have in your 10g won't be enough for the new tank.

Sounds like you're well on your way to a nice planted tank!

[DUSTIN323]

Well I was going to just mix it with regular gravel which will be fine I'm sure because on the bag it says you can mix it which of course I know if I bought another bag it would be best but I think I'll be fine with what I got in the 10g its alot in there.

[DUSTIN323]

I have finally decided I am goin to get the dual T-5 flourescent you had mentioned simpte I'll have 1.8 watts per gallon I've got a list of plants in mind here they are what do ya'll think for my setup:

Water sprite
Java fern
Java moss
Anubias nana
Anubias barteri
Temple
Cryptocoryne wendtii
Moss balls
Dwarf onion
Hornwort
Wisteria

I will probally get one more bag of flourite and combine it and the flourite that's in my ten gallon for the 20 gallon. I have a co2 system can't think of the brand just a little one for up to like 40 gallons and I'll get me a nice piece of driftwood to soften up the water and make it acidic. Also I found out the whole wpg thing you can use it as a general rule of thumb because usually the more watts(which is the power it's taking) gives off more lumens. But with technology rising you can have lower watts with more lumens like say a T-5 bulb I believe it has more lumens than a N.O. flourescent but 2 less watts.