Bansaw I would suggest that you look at these links
http://www.vegetablepharm.blogspot.com.au/p/dietary-fiber-info.html
http://drbganimalpharm.blogspot.de/2014/09/dont-take-resistant-starch-alone-and.html
and
http://www.drmyhill.co.uk/wiki/Fermentation_in_the_gut_and_CFS
http://drbganimalpharm.blogspot.de/2013/11/how-to-cure-sibo-small-intestinal-bowel_10.html
http://coolinginflammation.blogspot.com.au/2014/03/health-in-diagrams-i-gut-flora-and-diet.html
Its a big topic and takes a long time to understand, and its not as if everyone agrees of knows the "Truth" if there is one. Kind of like CFS.
I tried taking isolated fibre with the commercial probiotics recommended on the animalpharm site.
I really did not like raw potato starch, I tried it for a while based on everyone else's opinions and found that it made me worse. And I was taking it with green banana flour, acaia gum, psyllium etc. So I was not doing it in the worst way, the way that Animalpharm now advises against.
I also had a problem with one of those 10 strain probiotics that made me extremely photophobic for a couple of weeks: which was how long it took me to realise that I should I stop taking it.
My take away is to listen to yourself. Try things but don't keep taking anything that makes you feel worse.
I have found that what worked best for me is eating a diet which contains kombucha, beet kvass, fermented veges and foods that provide a large range of different types of fibre.
I roast a lot of vegetables at one time then cool them in the fridge to produce RS3. I then eat them with lots of greens and other cooked or raw vegetables in salads or added to soups/stews over the next few days.
I have some sort of fermented drink every day and eat fermented veges most days.
But I also have days where I cannot handle greens, or just want a kilo of raw carrots, or dates or something.
In the absence of perfect knowledge, I don't force myself to do things that I really don't want to do, and follow my strange whims.
The only isolated "fibre" I take is lactose, because though I cannot tolerate dairy at the moment (presumably the casein) I hope I will be able to in the future and I do not want to loose my lactase producing bacteria. It also is something I like, but only at about .5 - 1tsp per day.
Coming back from SIBO I have had to be careful about food intolerances, avoiding foods for a while and then retesting them.
And some of the reactions have been really bad, retesting hazelnuts and almonds was hell. As were chickpeas about 8 months ago but I retested them last month and now I can eat them.
I would also suggest that you might want to slowly increase the amount of fibre you eat. A quick increase can lead to a lot of gas, which can be painful and disturb your sleep.
I hear an interview with Terry Wahls in which she reccomended that people start with cooked and pureed foods, then cooked foods, then fermented foods etc.
You may also want to look into stomach acid. Myhill writes about this. But the stomach acid is meant to stop SIBO from happening. I had low stomach acid, which lead to reflux, which lead to my doctor giving my an H2 inhibitor to reduce my stomach acid!
I now take betaine hcl, and that seems to have improved things a lot.
I drink the pickle juice and fermented drinks between meals so that their probiotics are not killed by the acid.
I liked some of the commercial probiotics, I particularly liked
http://www.iherb.com/O-Donnell-Formulas-Flora-Balance-Flora-Balance-60-Capsules/6078 and
http://www.iherb.com/Advanced-Ortho...atural-Probiotic-Formula-90-Veggie-Caps/43463
The multi strains are probably not as interesting as your kefir, or some fermented veges which will bring a whole range of wild bacteria.
If you are not into the fermented vegetables I suggest you look into Sandor Katz
http://www.wildfermentation.com/ . I prefer to do my ferments in fido or le parfait jars, but Katz is a wonderful resource. I watched several of his lessons/talks on fermentation on youtube, and also bought one of his books .
I really hope this helps.