Good light in a planted aquarium is also important for keeping the aquarium healthy. As detritus breaks down into Ammonia, Nitrites and then to Nitrates, the plants will help absorb them and keep their overall concentrations closer to 0. A well lit, well planted aquarium will not only be beautiful but be more likely to be healthy too (not counting fish diseases of course).
Ideal light for aquarium plants is in the green and blue spectrum- reddish light promotes algae growth. In fluorescent light terms that means you want 6500K-10000K. Different people will tell you different things. The second thing to consider was the Watts/Gallon. I was at 3/4 (15 Watts / 20Gallons) of the wrong light. 2 Watts per gallon is considered to be a good, strong amount of light (adjust some for extra depth on a tank like this) Obviously what I have won't do.
So I thought about it and came up with the simplest and least expensive design I would think of that would give me a lot more light. I didn't think of making an instructible out of this until after I'd started, but I hope my pictures can still help. And if anyone has questions, just message me!
2 two-packs of Sylvania 13W 6500K micro-mini "Daylight" bulbs- $6.98/pack
(They also have 26 Watts, but I didn't get them. If I decide I want more light yet, I might try them. They
might get hotter though)
3 sockets with brackets and leads- $2.17/each
1 GFCI adapter- Ask and decide what you want. This is NOT necessary, but it could save your life. I bought one.- $15.28
Some tinfoil for a reflector
A small metal bolt, washer, lock washer, and nut
30 minutes to an hour, depending on your efficiency at hands on stuff.
Total- $20 some without the GFCI
$35 some with the GFCI
*Note that all this is is your doing and therefore you are responsible. I would only do this if you have a glass humidity shield. If humidity gets on this it will almost certainly ruin the light socket, and could potentially cause a short, meaning melting or a fire. So, be smart.
Step 1: Out With the Old, in With the New
Because it seemed convenient, I used two of the screw holes for two sockets, and only drilled one extra hole to mount the last socket.
Step 2: Wire the Leads
In text format, here is what I did:
1) Wire the power-in switch lead to a power-in lead
2) Wire all the white socket leads together, and connect the power out switch lead to this group- four wires together
3) Wire all the black socket leads together, and connect the power out line to this group- four wires together
I wanted this to be very secure so I chose to solder all the leads and then put a wire nut on them as an extra measure. I tucked all the wires under the aluminum rail, including the wire nuts.
Step 3: Put in the Lights and Foil and Test It!
Depending on your quality of wiring, your lights of choice, operating temperatures could get hot. It might melt, it might short, this can be dangerous. I set mine on two coffee mugs and let it go for a couple hours.
So give it a once-over eyeball, light it up, but don't leave the room for a few hours until it's reached its steady state operation. Then watch it some more. Make sure than when you reinstall it that it's protected from humidity!
Do your routine maintenance on the tank, clean off the algae, add some fertilizer if you want, maybe a CO2 system, and watch your plants go crazy! The advice given to me was to change these bulbs every 7 months. While they'll still work, they may not be emitting the same spectrum and algae may be more prone to growing.
Also important is how much light to provide. Leaving these on 10 hours a day (because I liked the light) I found that I was growing algae on the sides faster than I liked, so I cut it back to 6 hours. That seems to work pretty well. To find out how much light you need you'll just have to test it for approximately 2-3 weeks at a time after cleaning.