Leaving hydrometer in FV after 1st reading..

[neilos]

Just read a post where I got the impression that the author left his hydrometer in his FV after taking his first reading. I've been taking my first (technically 2nd I suppose) SG reading after about 4 days with a sanitised hydrometer. Could I just leave it in the FV so that I can take a reading every 24 hours or so?

[phildodd]

Absolutely, it's a much easier way of doing things, and means that you're not wasting beer by taking a sample...

[Manx Guy]

Hi!

is this practise suitable for lager fermenting?
I guess with a genuine lager yest you could throw the sanitised hydrometer in from the start as there is little foam head on the surface (?)

Cheers!

Guy

[fractureman]

I do it all the time with both of my FV's take the starting gravity before I add the yeast then just leave it in there

[trucker5774]

Unless I am planning another brew (no spare hydrometer anymore) I always leave it in the FV. I resist playing with it though and only check after about 4 days unless it is apparent that fermentation has not started (not the case with my current brew....)

[lancsSteve]

I used to do this but now prefer taking samples as:

1 - no matter what I did the hydrometer was always in the middle of a load of bubbles and almost impossible to read

2 - The 'sacrifice' of samples at 100ml a time (so maybe taking 4 of them) isn't much really and allows me to try the brew at different stages and get a feel for flavour changes and dropping sweetness as it ferments...

'Losing' a pint out of 40 and having a hydrometer I can use seems a worthwhile trade off.

Better to leave it in though than take it out and re-sanitise and put it back in as it'll never be fully sterile. Having a spare is a must as well in case you drop/break the only one whilst brewing which is easy to do and a pain to compensate for...

[Barm]

Opinions will be forever split on this!

For my 2p's worth: I did try leaving the hydro in, but like lancsSteve I found it was invariably covered in bubbles and/or bits of yeasty deposit - either of these can give a false reading.
I now use a 50p Wilko turkey baster to take and transfer my samples into a glass sample jar. Much easier to ensure everything's clean, and to read the hydro accurately (meant to be done from the side - not from above, so you can see the meniscus properly).

As for 'wasting beer' - there you have 2 words that should never exist in the same sentence....
Either 'sample' it yourself (a la lancsSteve), or just gently pour it back in!!! If your hydro, thermometer and jar are properly clean there's very little risk in this.

So no definitive right or wrong here: if you're confident in your hydro readings then go for it.