OK, something's not right with this DIY yeast mixture, (I think)

I have a Hagen system on my 29g. It has been on the tank for about 3 days. I am using DIY mixture of sugar (up to the line inside the canister), 1/2tea bread yeast and water.

Original stats on tank (before co2):
kH 35.8ppm (very soft water) I don't know why since all my other tanks are around 71 ppm
pH 7.0

For the first 2 days, not many bubbles and they were getting stuck on the ladder (I knew that the ladder needs a buildup of slime on it for the bubbles to flow freely).

This morning I noticed many more bubbles flowing (almost one after another). They are still getting stuck, but, I checked my pH and it's about 6.6. I also noticed that there's some yeast mixture bleeding up from the canister into the tube. Is that a bad thing?

Questions:

Should I add something to the tank to raise kH? (or the co2 canister, baking soda maybe)?

Do I have too much yeast in the canister (1/2tea)?

Should I run the aerator at night to gas off some of the co2?

OR, should I just wait and keep my eye on things and if the pH goes to low, phone back???

Thanks.

Thank you,

Should I open up the canister and add the baking soda now to the original mixture, or should I empty the canister and add a new yeast mixture, this time with the baking soda?

I'm still a little worried about the mixture rising from the canister into the tube. Does this happen with anyone's canister, and is it something I should be watching?