First time using RO water

[Brett3rThanU]

I just brewed an all-grain batch of Zombie Dust from the recipe posted on this forum (using US04) and decided to try brewing with RO water for the first time. I used the Bru'n Water spread sheet for a light pale beer to dial in the water chemistry I was after which ended up calling for 1 tsp of gypsum and about .25 tsp of calcium chloride in the mash, then the same for the sparge water. My OG was right on target so I suspect my mash pH was fine. Anyway, I pitched the yeast around 11pm Saturday night and fermentation was under way about 12 hours later. This morning it was bubbling like crazy, then all of sudden this evening I hardly see it bubbling at all. Fermentation temp is holding steady at 66-68F. I know RDWHAHB and all that, but is it possible the water chemistry could be halting fermentation or causing any problems for me? I've never had a fermentation fizzle out so quickly. Thanks.

 

[fun4stuff]

I just brewed an all-grain batch of Zombie Dust from the recipe posted on this forum (using US04) and decided to try brewing with RO water for the first time. I used the Bru'n Water spread sheet for a light pale beer to dial in the water chemistry I was after which ended up calling for 1 tsp of gypsum and about .25 tsp of calcium chloride in the mash, then the same for the sparge water. My OG was right on target so I suspect my mash pH was fine. Anyway, I pitched the yeast around 11pm Saturday night and fermentation was under way about 12 hours later. This morning it was bubbling like crazy, then all of sudden this evening I hardly see it bubbling at all. Fermentation temp is holding steady at 66-68F. I know RDWHAHB and all that, but is it possible the water chemistry could be halting fermentation or causing any problems for me? I've never had a fermentation fizzle out so quickly. Thanks.

i had a brew go from 1.082 to 1.020 in 2.5 days. Did you use a big starter? i bet youre fine. If its driving you nuts still this weekend, check sg.

 

[MagicMatt]

I know RDWHAHB and all that, but is it possible the water chemistry could be halting fermentation or causing any problems for me?

Not at all. The water chemistry really has noticeable effects in 2 areas of making beer: mashing, and taste.

Obviously salt additions will effect alkalinity of the mash water and thus influence efficiency of starch conversions. Since you say your OG came out spot on, you're fine here. In regards to taste, if the ratio of SO42- to Cl- is <1.0 you'll get a more bitter taste; if it is >1.0 it'll have more of a malty taste. Anything around 1.0 will be well balanced.

And yes, the yeast feed on the macro and micro nutrients in the water somewhat, but not enough to matter. They need oxygen and fermentable sugars primarily.

I'd say you're probably nearing the end of a quick primary! I've had that happen several times, where I hit my FG within 72 hours of pitching. If you use a secondary, I'd still leave it in the primary for another few days to make sure it cleans up. But other than that I'd say you're fine.

 

[Natdavis777]

Few questions:

1) is ambient temp 66-68F or is that the temp of the wort? If ambient temp, them fermentation temp is most likely higher, and can accelerate fermentation.

2) Is there still krausen? I never judge my beer by the bubbling. After 100+ batches I know my ferm schedules pretty well, and know I can judge a beer more on the krausen activity more than the bubbles. IE if you still have some krausen, and can visually see yeast activity in the carboy, regardless of bubbles, its still chugging away.

All in all, let it ride for a bit. Water chem only affects taste and extraction for the most part (can affect fermentation via wort pH). If it were going to affect the fermentation in a negative way, it wouldnt stop in the middle of the process (nor would it have taken off so fast). Finish the beer as you normally would.

Your mineral additions match my 5 gal batch profile for that recipe so so I assume you made a 5gal batch and mine have all turned out fine (one of my most frequent brews)

 

[Brett3rThanU]

Thanks guys. 66-68F is the temperature of the wort, not ambient.

I spent the last week reading about water and water additions and didn't recall seeing anything about it effecting fermentation. In all my 7 years of brewing I don't recall ever having the bubbling slow so soon, just wanted to see if my change of process (RO Water + salts) could be the root cause. Anyway, I'll just let it sit the remaining 2.5 weeks before I check the gravity and keg per usual.

 

[runningfarmer]

So4 is a monster and can seem short. I chase up fermentation temps for a higher attenuation. I have used bru'n water for a few years and is a good system for Ph. And flavor

 

[b-boy]

I've made that a few times.

I've always had really active fermentations up front. They die down quickly, but keep slowly bubbling for another week or so. It's happened all 4 times I've mad this.

I just assume it's part of the fermentation profile for the beer.

 

[Brett3rThanU]

You guys were right, it was fine. Checked the gravity yesterday and it was down to 1.015 which is where I expected it to be. Thanks.

 

[mabrungard]

You guys were right, it was fine. Checked the gravity yesterday and it was down to 1.015 which is where I expected it to be. Thanks.

Glad to hear it worked out. Of course, the proof is in the tasting.

As an aside, what was your mashing temperature? I'm assuming it was on the high side since the FG is a bit higher than what I expected. I prefer most of my beers to ferment a few more thousandths. That beer should still be fine.