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I was wondering if anybody had any positive experience with these kind of lights. I'm planning to get two 15-watt for my 15 gallon tank. This would add up to 45 watts since I already have a hood with a 15 watt fluorescent lamp.

P.S. my tank is planted but with only the fluorescent lamp it's not enough to grow that many plants.

So what do you guys think?

Edit - I'm planning to get the "daylight" ones. Are these screw-ins any good for plants? And how will my tank look? Does the tank look yellowish with these kind of lamps?

I've got 9 23w (8000k) screw in compact flouros over my 20 gal reef (you don't need anywhere near that amount of light for a planted tank, mind you... this is a reef), and they work fine. They aren't too horridly strong (read: low PAR), and they can't penetrate too deep (nothing over 2' deep), but they work fine.

For a 15 gal planted tank I'd think that two 15w ~6700k CF bulbs and a 15w flouro would work fine. Do try to get the 'Daylight' kind... read around on the box and see if you can find the K rating... 6700-7500 is arguably the best for plants. I've used them over planted tanks in the past with good results.

How are you going to mount them over the tank, though? Are you going to build a fixture? Do you have a screw-in fixture? Remember that you'll need some sort of reflector behind/above the bulbs to get decent light out of them. You CAN use the bulbs in standard desk lamps and in spotlights (as in what you'd use for studio photography... that's what I use for 4 of the bulbs on my reef tank), but then you've gotta have part of the tank uncovered to mount them.

It sounds like you're off to a good start--you know what you want, and you know what you want to do... now just figure out how you're going to do it and get at it

Good luck

I have had nothing but bad experiences with those.. I used to keep a 10 gallon quaratine tank, it was bought as one of those kits with the screw in light bulbs...I thought i would use the flor. bulbs since the fish would only be their for short periods of time... long story short. I went through about 4 of the name brand and about 10 of the lesser type.. none lasted more than a month... it could be my set up, or moisture or i dont know what but i have since have vowed to never used them again
how every results may vary..

I built my own hood already with some wood lying around my house. I painted the inside of the hood with white paint and I think I will just use CF plus the old hood with the fluorescent lamp.

I use CF to light my whole house and all of them have lasted pretty long so I will still try and see how long it will take to burn one

P.S. I checked my local hardware store and they have daylight bulbs but they don't have the kelvin temperature marked on them. Will they still work?

If it says daylight on it then they should be fine. Most 10g hoods come standard with a screw in socket. Usually this contains incandescents but they are easily replaced with pc bulbs. For that reason and the fact I have 3 10g tanks and a 5g with the same fixture I have used tons of screw in pc bulbs. From 5w up to 25w. They work perfectly fine. The only caution is that they don't seem to hold up to water spray as well as the incandescents. Even if they fit properly into the socket on a 10g hood they tend to give out sooner than incandescents if you use filters that disturb the surface alot like sponge filters. I would suggest using glass between the lights and water because even if you've added a waterproof edge to the socket or a splash gaurd it may not be enough. You need a solid layer between the bulbs and the water or the dampness does them in.

Sham, that problem can easily be resolved by hanging the bulbs vertically as opposed to laying them sideways. As long as the ballast (in the base of the thing)doesn't get wet, they're fine. I haven't had any problems with any of my vertically hanging CF's on my tanks... I've even had occasions where the bulb tips will droop into the water and be just fine.

It sounds like you've got the whole thing figured out, AH. I say throw a couple bulbs in it and see how it works

Be sure to post before/after pics

Problem is that would take alot more space and sockets than setting them sideways. Sideways means 2 bulbs fit on either side and lay flat. Much easier and less space used up if you just slide a piece of glass on top of the tank. However I can see why you'd do it that way for a marine tank where you want to keep the top open to keep the temp low and the oxygen level high. For a freshwater tank you generally want a glass top anyway and for a planted tank you nearly want the opposite as a marine tank with minimal oxygen exchange so all purposes are served by just adding on some glass.

Well, I made 2 hoods with the wood that I had. I don't know why but I just felt like doing it. The first one can house 3 bulbs but vertically. Originally I was going for 5 or even 6 because there was plenty of space to house them. But then the hood was kind of tall so I made another one with the exact same height as the hood that came with my tank. I decided to go with 2 bulbs but it had space for 3. I thought that 60 watts for a 15 gallon tank was too much of an overkill. Right now, Im using the fluorescent lamp and testing the hood with some fairly white CF that I got from the 99 cents store. The tank doesn't look neat or pretty and it's kind of like yellow but very bright. I'm going to get those "daylight" bulbs this week when I go out. See if the light looks better to my eye because right now, it's just awful.

P.S. the CF I'm using right now are soft white bulbs, I think. Probably with a temperature of 3000k. But hey, 99 cents each!! One more thing, right now my tank has 45 watts of light. Is that enough to grow anything on a 15 gallon tank? I heard Cf aren't as powerful as normal fluorescent lamps and that the watts per gallon rule doesn't apply for tanks smaller than 20 gallons.

CF's don't have as wide of coverage as normal tube flouros... but if you've got them spaced out evenly and you've got a normal flouro anyway, you're fine. The WPG rule isn't really an exact 'rule' anyway... it's a general guideline. Depth of the tank, PAR, K rating, height from tank, obstructions, etc, etc play a large role in determining light needs.

I think it'd be fair to say that you'll have 3wpg over the tank. If you want more light, all ya gotta do is switch out the 15's for some 25's (or if you want to go crazy and if you've got the space, they do make a 65w screw in CF )

Yea. That's true. Thats the good thing about CF. You can change the bulbs and there are a wide range of CF out there. I can always go extreme and get a 200 watt CF

http://img.alibaba.com/photo/51189050/Compact_Fluorescent_Lamp.jpg

With a single one of those I wouldn't need anything else

To my knowledge, they don't make a 200w CF bulb. They DO make a 200w equivalent (and a 300w equivalent... that's the 65w), though...

But yes, CF's are great because you can put any wattage bulb in there... they've got cheap built-in ballasts so you don't have to worry about buying a big expensive ballast and then you can't upgrade your lighting without replacing it...

I've had two 13w screw in florescents on my 10g for months and they work great. Cool white is too yellow, daylight is perfect. Before that I had cool whites for over a year, I've never had a bulb fail. Plants are doing awesomely. My only complaint is that it's hard to get the bulb screwed in all the way with the plastic seal thing around the socket like my hood has. But it eventually goes in if you're careful.