[scags]

So I am thinking of using those screw in spiral power saver bulbs. Does anyone know how well they work for growing plants?? Specifically Brazil Pennywort,HC, Bacopa, Rotala, maybe some needle leaf ludwiga.

I have read a few of the other threads.

I will be lighting a 20g, DIY CO2, soil substrate with high CEC. I thought about trying the spiral bulbs (6500k) in cheap metallic reflector pendants.

Anyone have some experience with these bulbs?

 

[Jadelin]

6500K spiral compact fluorescent bulbs (CFL) should work just fine to grow plants. That's basically what I'm using on my tanks.

 

[sevenyearnight]

I have those on my 10 gallon and they are great. I would suggest having the bulbs parallel with the water surface instead of perpendicular.

 

[scags]

Thanks Jadelin. How many are you using and what are your tank specs?

 

[scags]

Interesting SevenYearnight. I didn't even think of that but it makes total sense.

 

[Jadelin]

On my 29 gallon I'm using four 13 watts and on my 10 g two 9 watts. This is giving me good low light, enough to grow crypts, java fern, pennywort, H. polysperma, hornwort, and mosses. I also have an ozelot sword that is growing VERY slowly (I think it would like more light). You'd probably want to get more wattage to grow some of the plants you have.

In regards to the positioning, I've actually heard that you get more light if you position them vertically (perpendicular) rather than horizontally; more of the light is lost, apparently, if you have them horizontally. I have them horizontally in my 29 and vertically (desk lamps) in my 10, and the 10 does seem to get more light, although it's also a shallower tank.

 

[2in10]

I have those on my 10 gallon and they are great. I would suggest having the bulbs parallel with the water surface instead of perpendicular.

The bulbs lighting efficiency is reduced when placed parallel to the surface. They are designed to give the most light when perpendicular.

 

[sevenyearnight]

The bulbs lighting efficiency is reduced when placed parallel to the surface. They are designed to give the most light when perpendicular.

I have been mislead! Darn you intrawebz!
Thanks for that correction, although I can't apply it to my tank since it's how the hood is designed

 

[2in10]

I have been mislead! Darn you intrawebz!
Thanks for that correction, although I can't apply it to my tank since it's how the hood is designed

Bummer, if the fixture has a good reflector it probably doesn't hurt too much with the bulbs oriented parallel.

 

[Hoppy]

http://www.plantedtank.net/forums/lighting/85667-par-data-spiral-power-saver-bulbs.html

 

[Jadelin]

Bummer, if the fixture has a good reflector it probably doesn't hurt too much with the bulbs oriented parallel.

Yeah, if your plants are doing fine, that's the main thing. The nice thing about CFL is that it's so easy to upgrade the lighting by just buying bigger bulbs (as long as they fit), so if you think too much of the light is being lost you could go with stronger bulbs.

My 29 gallon has 4 CFL bulbs that are horizontal (DIY inside an old strip light) and stuff is doing fine. +1 on reflectors; they help a lot, and they help to redirect and put to use that light that would otherwise not be going into your tank. Even painting the inside of your fixture white helps a lot; that's what i did and could visually tell the difference from before.