Airlock question

My grape wine seemed to have stopped bubbling. The water in the S airlock looks like its being sucked back inside the carboy. Is that normal? Is this the stage they call bulk storage? I'm going to rack it for the second time.

I don't do wine, so this suggestion may be bad for you... But I use vodka in the airlock for that exact reason. Water, over time, can harbour nasties that can infect a batch. Very little can live in vodka (the cheapo stuff) and if you get suckback then it only adds a tiny amount of ABV to your beverage.

As for the suckback, that DOES happen due to several reasons. The one more common for me is when I move the fermenter and the bucket/Better Bottle flexes.

The second most common reason is temp changes. Everything changes volume when it heats or cools, and the liquid you're fermenting is no exception. As the volumes increase they create suckback.

In either case, it doesn't spell disaster.

Cool, thanks for the tip and advise. I thought something went wrong with the water being sucked back in. The airlock is still full and don't think it sucked any in, it just sucked it to the one side.

After I rack, i'll fill the airlock with vodka. Will it continue to bubble after I rack?

It may, or it may not, depends on how finished it is... primary will last anywhere from a week to a month depending on what your recipe looks like, then secondary should be a couple weeks to a month again... then you will want to rack it again into bulk aging, and that when you set it in your closet and forget about it for as long as possible...

Aging also depends in the recipe and ABV, it could be anywhere from 3 months to a couple years... you wine also may not need to be aged, if it is from a kit... I know some kits do not call for any aging at all...

I racked it and topped it off with the extra 1.5 gallon I had on hand. There is about 1.5" of head space and its still bubbling slowly. I made sure I sterilized everything that came in contact with the wine.

I took a SG reading of 1.010. I tasted the test tube of wine and was very surprised of the taste. It actually tasted like wine and had a hint of kick to it, LOL. I held the tube against some light and its very clear with no haze. I think its on its way for bulk aging.

Temp changes as stated can suck the fluid from the lock back. Also a drop in atmospheric pressure such as when a storm front comes through can do it. If you have any k-meta or Na meta, use that in the lock. No need to waste good vodka. Plus, if the sulfite solution gets sucked into the wine it will only help the wine as you need sulfite's to protect the wine.

With that SG you probably still have fermentation going. If fermenting to dry you want to get the SG below 1.00 and then you can add sulfite's and sorbate to stabilize the wine and prevent re-fermentation after you have racked the wine off any gross lees and let it bulk age. If you have a test kit during bulk aging check the sulfite levels periodically to assure the levels are suitable for the type of wine. You will need to know the pH to get an accurate sulfite level.