The "Natural Daylight" tube should be perfect. You've linked the "Tropical Sunlight" which is going to give a purplish hue. You mentioned two tubes, one white and one blue; you may have one of each of these now, in which case that will work. But two tubes over a 3-foot tank is a lot of light, and this creates problems because there have to be sufficient nutrients to balance or algae will take hold.
Now that we've gone this far, I would suggest a good comprehensive plant fertilizer (liquid). Seachem's Flourish Comprehensive Supplement for the Planted Aquarium
is about the best I've used. There is one available in the UK, name slips my mind, that I looked at for another member a while back and I thought it would be OK. Have a look for the Flourish, if they have it, get it; a half-teaspoon once or maybe twice a week in a 30g is all you need so it lasts a long time. If you can't get Flourish [and make sure it is the exact name I gave, Seachem makes several plant products in the Flourish line] let me know what you can get, with a internet site link just in case
and I'll take a look.
You are going to need fertilizer with this much light. And I would have the light on for 9 hours each day; a common lamp timer from the hardware store is the best way to get this. With the fertilizer this should work, although if algae develops you could reduce the duration. I suspect you can't remove one of the tubes and still have the other light; most fixtures need both tubes in. But you could try this and see, as one tube (the natural daylight) on for 12 hours would prob be fine.
The temp is fine for tropical community aquaria. Just be prepared to lose the Egeria, though again it may rebound. This plant is sometimes used in goldfish tanks due to the cooler water.