I have a 65 gallon aquarium with dimensions 36"x18"x24" (LxWxH).

Since the aquarium is so tall, I am having trouble deciding what type of lighting to choose.

I want the tank to be low-tech (Walstad-esque) in that it will be heavily planted with low to moderate light plants, with slow, steady growth. Definitely no CO2, (hopefully) no ferts, dirt substrate... you get the deal.

Right now, I am thinking this fixture will work nicely (2x 39w T5 6500 K). However, it will only put me at 1.2 WPG. Will the fact that it is T5HO help overcome this shortcoming? They make the same fixture with 4 bulbs, but on another forum they said it would be way too much light for a low-tech tank.

If anyone has experience with Walstad, NPT, El Natural, etc. type tanks - please give me some advice on lighting considerations. Keep in mind the depth of the tank. I should also mention that the tank will get a moderate to low amount of indirect sunlight.