Rapt Pill

[HazyNick]

Hi all

I have been using rapt pill for a number of brews now and I like it. It provides me with the information I want and allows me to monitor my brew easily.

The only issue I seem to have is the difference in the OG reading compared to my Hydrometer.

For example, my current brew, which I took a reading of at room temperature as I transferred to my fermenter was 1046. I add my yeast and the Pill, seal up and connect the RAPT controller and my OG reading on the controller is 1038.

This has happened on my last few brews, so I advertise my ABV as "between x-y".

Does anyone else have the same issue and is so is there something I need to do with the pill? I tend to use the reading of my hydrometer rather than the pill for my OG as this method has never let me down, however it does seem strange that there is a 8 point difference straight away.

Cheers
Nick.

 

[janeri]

Have you calibrated it?

My Pills were quite a bit off before I calibrated them. In any case, I use them only to get an impression of activity and progress, not for exact measurements. They will usually be disturbed by krausen asf, so accuracy will be lost even if they are calibrated.

Jan

 

[HazyNick]

Thanks Jan

Yes calibrated prior to first use, I have only used it for 5 brews so far.

Good to know that the manual hydrometer is still the way to go.

Cheers
Nick.

 

[KegLand-com-au]

krausen does effect all of these hydrometers. I am sure if you were to float your standard hydrometer in the fermenter the krausen would stick to the outside of this too and also put the readings out.

One way to combat krausen sticking to these floating devices is to shake the fermenter from time to time. Wort washing over the pill seems to wash off the chunks of krausen and eventually this krausen sinks to the bottom of the fermenter. It's obviously easier if you have a clear fermenter like the FermZilla so you can see if you have krausen stuck to the surface and shake accordingly.

With that said it's not the absolute figure that is generally used for determining when to do a diacetyl rest or crash chill. What we are generally looking for is gravity change. If the gravity decrease is slowing down then increase the temp for the diacetyl rest. If the gravity change completely stops then it's time for the crash chill. So even if krausen was stuck on the pill and you did not want to shake the fermenter I would be mainly looking at the gravity change rather than the absolute values.