[IUnknown]

I agree with carlos to get the 20 high. You want a tank that is close to the following ratio, 2:1:1.

Should I have two 6500k bulbs instead of subbing in the 10000?

I'd go for two 6500K bulbs. If you can, get one 6500K and one 9325°K Super Daylight (55W). 65W and 55W are usually interchangeable, I would use 55W on that fixture.

I wouldn't worry about flooding with an external filter. If you have money get a eheim that will turn the tank over 8-9 times an hour,IMO.

With the Co2, I like the JBJ. Maybe just get the regulator and down the road get the Milwaukee controller. I personally like to get things bits at a time. Test kit will be good enough to let you know you are within range. After a couple of months of learning you'll be ready for more control. Just run it into the canister. I did this for awhile without any problems.

http://aquascapingjournals.com/journals/10_gallon_aquascaping_journal.htm

 

[IUnknown]

Do you think it's worth the extra $$ ($20 or so) and the loss in intensity (2x65 vs 2x55) to go with AH supply?

I know the AH supply ballast are interchangeable (65W and 55W). So I would start off with the 55W and if your not happy you can just get new bulbs.

One thing that is neat to do with the bowfronts is to flip it around so that the bow is in the back. This gives you more room to aquacape with, you don't have the distortion from the bow of the tank, and you don't have to deal with curving the wood for the canopy.

I know you have to trim the plants a lot, provide more CO2 and more macronutrients and trace elements....but is there anything else?

Deal with a lot of algae, weekly. Its harder to balance, and things can go out of whack easier. It gets frustrating if you don't know what to do. Maybe start off with one bulb on, and when things get established, turn them both on. If it's a new setup its going to take a month for the substrate to mature and for the plants to get established. More light will just cause more algae and make it harder for the plants to start off.

 

[IUnknown]

Sorry, yeah I think Jeff is right. Call and check to see if you can run the 65W on the 55W ballast.