You have to be a bit more patient Toney.
Have to remember this is a worldwide forum and lots of folks are on different timezones.
But as to your query if using ballast with what looks like T5 lamp fittings, will work perfectly fine as long as the ballast are suitable for the light wattage you want to use.
As for one or two tubes, this depends on how big and how deep your tank is, also will this be a high tech set up using Co2, ferts and root tabs etc?
If so then two tubes would be miniumum, but if its a low tech set up then one tube will be ok, just depends how dim or bright the tank you want it at. The higher the kelvin rating, the brighter and more intense the light will be.
One of my tank has 2 tubes and thats a low tech set up which i add ferts and root tabs but no co2. The tubes themselves are low wattage and if remember right one is about 6,700k and the other is normal daylight 10,000k. Those are T8 btw, so the light intensity is much less than those T5 tubes.
Am sure there are a few DIY threads about modifying light hoods to suit as many folks have done this modification to their tank light hoods when t5's came out also for those who want to convert to LEDs as well.
