Why Not? (a hydrometer question)

I brew small one gallon and recently started using a refractometer. I just had a random thought: Why not just have a few extra hydrometers and leave them in the carboy? This scheme would probably be better suited for the secondary, but you wouldn't have to keep opening up you r carboy to take samples.

Thoughts? Hydrometers aren't that expensive....

You wouldn't be able to read them with the krausen coating them. I thought of this before coming to that conclusion.

In addition to the krausen obstructing your view, I wouldn't trust the reading unless I could make sure there were no bubbles formed on it pushing it up or other debris attached pulling it down.

That's why I was thinking it would be better to drop it in after the transfer.

The bubble point id a good one. Thanks for the points, not something I'll do...but just thought if get some input

If it is glass hydrometer I would be afraid of breaking it when I tried to get it out. They can be pretty fragile.

All you have to do is draw your OG sample after adding the yeast and set it next to the carboy with the hydrometer in it. If the hydrometer gets covered with krausen, just pull it out and clean it. Yes, the sample might go weird on you, but it does make it easy to monitor the fermentation. Once the sample reaches the FG, clean everything and draw a new sample.

I've noticed that the sample tube tends to ferment a bit faster than the main carboy, but the FG will be the same.