We are all different. I can eat buckwheat only rarely. Buckwheat is technically not a grain and it has no gluten. But it does raise my blood sugar, which is not good for candida.

If you have candida, sugars and starches feed candida. This means all carbs, including fruit. It all depends on how bad you want to get rid of the candida how strict you are on your diet. There is a big difference in having buckwheat once a month or even brown rice once or twice a month and having a starch like buckwheat or rice every day.

Some may only need maintenance and can have a little more grain, but with active frequent yeast problems, or a family history of candida or diabetes, I would be really strict and take lots of probiotics and Colloidal Silver to help my body get rid of it.

There are several issues rolled into one here. It's why the answer is highly individual.
The basic principle of the candida diet is to reduce the food the candida needs to thrive--sugar.
Carbs are sugar, only they are more slowly absorbed than the regular sugars--saccharose, fructose,lactose etc.
The problem is that sugars are absolutely necessary for the proper functioning of the human body. There are also present in lots of foods--not only grains but fruit and veggies.
So you should not and cannot really eliminate Sugar from your diet; you just want to limit your intake so that the physiological needs of your body are met. The modern diet is way too rich in sugar/carbs, it's not healthy for human beings but it's perfect for candida--and other bacterias and parasites as well.
So practically, if candida is your only problem,
- you must eliminate foods containing saccharose--regular Sugar you find in sodas, candies and pastries--and fructose--that means no fruit when you start the diet.
- you must limit carbs--ALL grains, wether it's wheat, rice, etc.

However, candida usually comes with a form of IBS--the intestinal lining is inflamed and reactive from the candida infection--gluten/wheat must be avoided in that case because they are known to aggravate this inflamation.
Candida also comes with allergies. Allergies are highly individual however there are substances that are known to be allergenic--wheat, milk, eggs, nuts, fish and shellfish, nightshades veggies, etc--while rice is a non allergenic food. If you are allergic, chances are you are going to be allergic to some or all the above substances, but not to rice. That's why brown rice is recommended for candida sufferers, while wheat is not. White rice might be even prefered to brown rice because it's better tolerated by some.
In any case, when it comes to graIns, you have to figure out which grains you tolerate based on a trial and error method; in other words, listen to what your body tells you.