Hydrometer reading changes over time

[RedHouse]

I checked my FG on a Nut Brown Ale a couple of days ago. When I initially checked it, the FG was 1.016(supposed to be at 1.013...I missed a bit) I let the hydrometer sit in the beer(in sample tube) for a few hours, when I checked it again, the reading was 1.020.

I decided to check it with water. Initial reading was 1.000 Let it sit overnight, and it read 1.004

Anybody know why this might happen? I'm not sure if I should trust it or not now.

 

[hector]

Was the sample's Temperature always at the calibrating Temperature ?!

As you leave the sample in the Tube for such a long time , then its Temperature will rise and the Hydrometer is not

supposed to show you the same reading .

Hector

 

[RedHouse]

Temp remained the same(room temp at approx 67°). In fact, after I pulled the hyd out of the water sample today, I put it back in, and it's reading 1.000 again. I'm going to leave it in for awhile and see if it still happens.

I don't usually leave it in the sample for such an extended period, but for some reason, I noted the FG and just left the hyd in the sample for about five hours or so.

 

[JPicasso]

I'm guessing the hydro is sticking to the side of the tube. Don't rely on a reading where the thing has been in the tube for an extended period. I always give it a spin to make sure it's not sticking if I've been waiting for it to cool or whatever.

They say that the container the hydro comes in isn't ideal for actually taking mreasurements, we should be using a slightly wider vessle, but I don't listen to them, just make sure it's not touching.

 

[SpanishCastleAle]

Maybe bubbles are forming on it, causing it to float more. Give it a spin and see if that brings it back.

 

[ChshreCat]

+1 on bubbles or sticking to the side. My first and second thought when reading the OP.

 

[homebrewedipa]

+1 on bubbles or sticking to the side. My first and second thought when reading the OP.

Yup, that's my bet too. I always take a couple readings after spinning the hydrometer and bobbing it up and down. Make sure the tube is perfectly vertical and that no part of the hydrometer is touching anything except liquid.

 

[samc]

Simple solution, test at the correct temp, pull the hydro and drink the sample fast. Ignorance is bliss in this situation. It ranks up with having several thermometers give you different readings.

 

[RedHouse]

Simple solution, test at the correct temp, pull the hydro and drink the sample fast. Ignorance is bliss in this situation. It ranks up with having several thermometers give you different readings.

I like this answer!

Thanks guys....since it's reading correctly in water, I'll just test quickly and get rid of the sample!

I'll do one last FG check on that brown ale before I bottle it tonight....won't make the mistake of leaving the hydro in there. I'm betting it was sticking to the cylinder or bubbles.

Now....back to drinking my Haus Pale Ale

 

[malweth]

Sounds like a bad case of reverse-fermentation to me! Dump the beer!

 

[RedHouse]

No way dude.....that's alcohol abuse!

 

[ChshreCat]

Never throw out reverse fermented beer because drinking it gets you sober. See, you get hammered on the regular stuff, drink a few reverse-beers at the end of the night and then you don't get the hangover the next morning because you go to bed sober.