179 replies to this topic

[Big Nake]

The day this went down I filled a bucket with 2 gallons of untreated well water known to have iron in it. Then I dropped in a a solid pinch of Brewtan B. Waited several hours and it was still clear. I forgot all about it until last night when I went to dump it and it looked like this. Maybe a slow reaction at room temp?

Umm. You have a weed growing between your bricks!

So how long has that bucket been sitting there? Could it just be turning green naturally (mold, algae)? Occasionally when my rain barrel is empty I'll fill up buckets with regular source water and let them sit. If they sit for a few days, they'll start getting greenish naturally.

[positiveContact]

Doesn't heat usually speed up chemical reactions?

[neddles]

Umm. You have a weed growing between your bricks!

So how long has that bucket been sitting there? Could it just be turning green naturally (mold, algae)? Occasionally when my rain barrel is empty I'll fill up buckets with regular source water and let them sit. If they sit for a few days, they'll start getting greenish naturally.

My well water does not grow algae.

 

That is the crappy patio under my deck where I brew.  Original owner did it himself, as you can tell.

 

Doesn't heat usually speed up chemical reactions?

 

In general.

Edited by neddles, 08 November 2016 - 07:52 AM.

[Big Nake]

My well water does not grow algae.

If you put your well water into a bucket and left it outside for days it wouldn't grow algae? I don't understand.

[HVB]

If you put your well water into a bucket and left it outside for days it wouldn't grow algae? I don't understand.

mine does not.

[Big Nake]

mine does not.

Huh. I guess I thought that anything in the air would get into that water as long as the water didn't have anything to protect it. My source water is loaded with chlorine so algae wouldn't grow right away but it would eventually. So if either of you had a pool in your backyard you wouldn't have to chlorinate it to keep algae from growing?

[neddles]

It's not going to grow algae in a bucket in my dark basement over 3 days time at 60F. My well water is almost completely devoid of minerals except for iron. If left in my yard in summer it would eventually grow algae, I think.

[Big Nake]

It's not going to grow algae in a bucket in my dark basement over 3 days time at 60F. My well water is almost completely devoid of minerals except for iron. If left in my yard in summer it would eventually grow algae, I think.

Oh, I didn't know it was in your basement... I thought that you left it outside. The color of that water looks like water I would leave in a bucket over a 3-4 day period and that's in the spring/summer and in my backyard. So does that mean that the brewtan is combining with the iron in your water and turning it green? How do you prepare brewing water for your batches? RO?

[neddles]

Oh, I didn't know it was in your basement... I thought that you left it outside. The color of that water looks like water I would leave in a bucket over a 3-4 day period and that's in the spring/summer and in my backyard. So does that mean that the brewtan is combining with the iron in your water and turning it green? How do you prepare brewing water for your batches? RO?

I am speculating that is what happened. I brew with RO only.

[Big Nake]

I wonder if when I send my source water through a carbon filter if I strip out some amount of iron. I would think that more people would have experienced this already but maybe there aren't that many people with raised levels of iron or many people use RO to brew. Seems unusual that this is the first time we're hearing of it.

[positiveContact]

I wonder if when I send my source water through a carbon filter if I strip out some amount of iron. I would think that more people would have experienced this already but maybe there aren't that many people with raised levels of iron or many people use RO to brew. Seems unusual that this is the first time we're hearing of it.

 

if you mixed the brewtan in right before mashing in you'd likely never notice.  it takes some time for the water to turn green at my house.  simply due to the way I mash in my water sits for 20-30 mins before I put the grain in.  in my case I put the brewtan in while I was heating the water up so it had some time to react.

[Big Nake]

I heat 5 gallons of strike water and just as I turn on the heat, I add my acid, any CaCl and CaSO4 and the ¼ tsp of brewtan. Then it takes a good 30-40 minutes to heat to about 160° but I have never seen this color. Sure, my heating kettle is a bit dark from all the use but then I pour it out into my MT and it has never had any color to it whatsoever... it looks completely clear. I'm sure there's a reasonable explanation and it would be great if it were "no big deal" but I wonder what a very pale beer like a helles or a pilsner would look like with that tint in the water... or would the color drop out?

[positiveContact]

I heat 5 gallons of strike water and just as I turn on the heat, I add my acid, any CaCl and CaSO4 and the ¼ tsp of brewtan. Then it takes a good 30-40 minutes to heat to about 160° but I have never seen this color. Sure, my heating kettle is a bit dark from all the use but then I pour it out into my MT and it has never had any color to it whatsoever... it looks completely clear. I'm sure there's a reasonable explanation and it would be great if it were "no big deal" but I wonder what a very pale beer like a helles or a pilsner would look like with that tint in the water... or would the color drop out?

 

I believe it would drop out.  in fact I'm pretty sure there was "stuff" settling to the bottom of the strike water before I dumped the first round of it.  I have to think it will settle in the fermentor as well.

[Big Nake]

We need a chemist in here. Paging Mr. Brauer. Would Mr. Beer Brauer please report to the beer forum? I already assume that I'll kill myself with some sort of metallic poisoning, Starsan poisoning, using the wrong type of CO2 and put myself in the hospital and all kinds of other things... I don't need green water in the equation. Hopefully it's nothing and brewtan is doing exactly what it should be doing... but I'd like to know what's happening.

[Brauer]

I might have answered this above. It should precipitate out. It is listed as insoluble in water, in the Merck Index.

I can't find any toxicity data, but I wouldn't expect it to be any more toxic than the iron. Probably less, once it drops out.

[dmtaylor]

Doesn't heat usually speed up chemical reactions?

 

Yes, this is known as Arrhenius law.  A rule of thumb associated with this is that reaction rates generally tend to double for every 10 degrees C (or approximately every 20 degrees F).  So..... at 70 F vs. 150 F, that's an 80 F difference, which means the reaction rate is 16 times slower at 70 F than at 150 F.  Approximately.

 

I am not a chemist but I do have a bachelor's in chemical engineering.  But that was a looooooong time ago.

Edited by dmtaylor, 11 November 2016 - 06:48 PM.

[neddles]

The water in the pic I posted above got even darker green over the next 2 days before dumping it.

[positiveContact]

The water in the pic I posted above got even darker green over the next 2 days before dumping it.

 

did it change to a more dark green/gray/brown color?  that seems like where mine was headed.  did you notice any stuff settling out?

[Big Nake]

The water in the pic I posted above got even darker green over the next 2 days before dumping it.

The algae was multiplying!

[neddles]

did it change to a more dark green/gray/brown color? that seems like where mine was headed. did you notice any stuff settling out?

Yeah a similar color to how it was in the other pic, just darker.