Starter size for weiss experiment

I've had some fantastic results with my hefeweizen's and some fantastic flops. This Saturday I'm preparing to do a double brew day with 2 different Weiss recipes. One is the recipe I've been using and has won an award, but it is also the recipe I've had giant flops with. The first time brewing it was last spring and I pitched the tube of WLP 300 and fermented it in our walk in pantry... Well the temp got a little high, up to 80 ambient... and it was a banana bomb. Then 2 weeks later the banana faded and out came some undesirable esters. The second round of brewing was in a room in our basement, at about 72, and open fermented this one had markedly less banana, but was very complex and good. This one won a local competition for it's class. The third round I tried again, but with RO water, with a bit of gypsum added and servomyaces pill. Yuck. Almost citrusy, and huge sulphur character. I read a little more into "brewing better beer," and learned that gypsum will accent the harsh sulphur, and I should use CaCl instead. Thanks Gordon! Side note: don't follow the water additions guide in "beer captured", it's wrong. I also determined that even though I haven't had a blown airlock, I need much more headspace for my Weiss' to cut any sulphur character that's there. So my situation is this, I'm brewing a Weiss experiment... 2 different grain bills in 3 gal batches. I'm going to follow the same mash schedule and boil additions. Same water (RO with CaCl) and yeast (WLP300) as well.

My goal is a balanced beer, with no flaws. A good amount of clove and banana. What I hope to determine is what grain bill works best to get the exact profile that my BF and I like best. So where I need help is this. I've read a lot in the last few days about pitching rates and fermentation temps and their effect on ester and phenol production, only thing is most of it is conflicting. What I gain from it is, underpitch, but only by a little. Overpitching will result in loss of Weiss character, but underpitching severely will cause higher levels of undesirable esters. Aerate, but not a lot. My goal is to pitch at 65 then put in my 65 deg basement room, and hopefully the fermentation will land at about 70-72 degrees at it's peak. I plan on open fermenting during high krausen for about 48 hours, as I've done with a few other beers and LOVED. What I'm hoping you can help me with is my pitching rate, and starter size. I think that if the yeast are woken up, there is a better chance I will get the profile I'm looking for. White labs page says tubes have 70-140 billion cells. The calculator for each 3-gal recipe says pitch 120 billion cells. But knowing what I do, I think 90-100 billion cells will be what I want to aim for with each batch. Since I want to save $6.99 on a second tube, exactly how much of a starter should I make to get in the right range~ 200 billion split into the 2 3-gal batches? Please give specifics here. Amount of water and wheat DME?

Also anyone with concrete advice on getting that balance can feel free to add to the conversation. I know there is a lot on this site about temp and ester/phenol production, and I've read most of it, but as I said a lot of it is conflicting. And the variables are many. For those of you who have read Gordon Strong's book, I'm following his step/decoction mash schedule for his hefe. It's pretty similar to the schedule I used last time, but I think the servo pill and gypsum killed that batch. I'll be using the regular wyeast nutrient in standard rate for the experiment.

1 liter of water, 100 grams of DME should get you in the 200 billion range. i don't bother with mineral additions for a hefeweizen, i filter my tap water for chlorine and it works fine for me.

Starter size will depend on your brew OG, whatever size you need, just make the starter gravity around 1.040 for any size beer. Also it doesn't have to be wheat for the starter, anything with maltose, you are simply building yeast so regular (barley) dme will work fine.

For the water I would suggest going back to the water used in your second batch.

Brew on my friend

Thanks,
Going back to the water from the second batch is too risky. It's spring water I was collecting at a local spring. Found out it's super hard. TDS in the 400+ range. I liked the second batch, but I still wasn't satisfied with it, even though it won. Our straight city water is pretty gross, so now I have a 4-stage reverse osmosis filter on it. The water is pretty barren at this point. Following Mr. Strong's advice with the .5 tsp CaCl for my 3-gal sized batch with RO water seems like a good bet.

Estimated OG is 1.051 for each batch.

Well, I never understood the whole "litres per starter" thing because there are so many variables when it comes to fermentation. The only sure way I know to tell how many billion yeast cells you have in a given wort is with a hemocytometer, microscope, etc.

That being said, Mrmalty.com says for 200b cells with one yeast pack at a small growth factor you need 2 litres of starter, all this of course with the other parameters that I have in my mrmalty settings.

Update: I used 100 g wheat DME and 1L water. Made my starter Tuesday night. Brewed up my 2 batches on Saturday. Pitched both Saturday night at 7 pm. Airlock activity started before 10 am Sunday. Opened them up (for open fermentation) this morning at 7 am.

What I've learned: I was not aerating enough before now. It's amazing what the yeasties like... Good food and plenty of oxygen. The airlock smells were very banana AND clove. In the past it was much more fruity, and sulphury. I am convinced that these WILL be my best batches yet.