It's been a couple days since I got the clone...

I would go with plain, room temperature tap water.

So what kind of water would be easiest? I have 4 clones that I'll water today because the top soil is getting dry. I've been using distilled water with a pH of 6.4

Yeah, distilled water is probably not a good idea for plants, especially young ones. Due to being distilled, it contains zero dissolved mineral salts and if used for plant irrigation, it can literally "suck" out the dissolved minerals contained in your plants cells and lead to wilting, plant collapse and even death to young or fragile plants. Just as reverse osmosis water, which is different to distilled water but has the same result of removed dissolved mineral salts, giving your plants the distilled water can cause reverse osmosis with your plants being the new source of dissolved mineral salts. You need to water enough that water comes out of the bottom of the pots and try and maintain moist soil, rather than wet and not water again until the first inch or so of the top of the soil feels dry when you stick your finger in. Your finger is really the most effective moisture meter! If the soil is too dry or only moist near the plant, she will not send roots into the dry areas, slowing growth and preventing nutrient availability. I would guess around a litre or so each time you water in those sized pots, but this can vary depending on temps and/or where the pots are in relation to air flow. Have a look at my diary "Cannabis Conundrums" for some photos of a 3 week old seedling with its roots exposed and this may give you an idea as to why deep watering is essential, even for young plants. There are also some more pictures there that will show some other weird and wonderful things cannabis plants are capable of doing, including some pictures on how to identify male and female flowers/plants and hermaphrodites too. Good luck with your grow.! ... Organoman.

Thanks for the advice @ORGANOMAN !! I will hold off on FF Nutes and CalMag for a couple weeks. I'll keep pH'ing the distilled water. How much should I water everyday using a 1gl fabric pot?