1. Do you leave the top of the primary fermenter open so it can breathe air in? I've seen it both airlocked and left open.
2. Do you let the primary fermentation go a given number of days or just whenever it stops fermention aggressively?

Cover with a towel to keep bugs out.

Let it get slowed down before moving to secondary so your carboy doesn't go off like a volcano. Could ferment fast and be ready to move to secondary in a few days or could take a week or more.

What are you fermenting in,,Carboys,,Barrels? Either way,,,use a one way air lock.It lets air out,but no air or bugs can get in.Its like the trap under your sink,,but smaller and made for wine fermenting.I let that go until I can not see visualy any more fermentation,,,then I "Rack" my carboys into a clean one.I siphon from the top down so as not to pick up the dead yeast and sediment from the bottom of the original carboy.

I've read that the fermentation process requires oxygen or fresh air to ferment properly. I'm confused.

I'm just learning. I don't know nothing but there's alot of info that contradicts each other.

Needs oxygen to reproduce during primary. When it goes into secondary it's anaerobic that produces the alcohol.

Okay so right or wrong I just took the balloons off of about 15 one gallon jugs of fermenting wine at different stages. I covered them with cheesecloth held on with rubber bands. I'll sit tight until I can't see active fermentation, then I'll siphon into clean jugs and leave the sediment at the bottom of the primary jug.
I've finished a gallon of pineapple which was surprisingly good, a gallon of apple, and two gallons of grape. I was eager to drink some so none of it was aged at all. Now I'm letting some sit and age so the secondary sediment can settle to the bottom and the wine will clear up hopefully. I'm thinking that frozen juice concentrate works better than the juice off the shelf in jugs.

No no no, Don't let the air get to it after it has been in the secondary. You will have oxidized wine that tastes like crap.

Gary, you need to get some airlocks, an assortment of solid bungs, and a good beginners wine book! There is still some trial and error, but it cuts the curve tremendously!

The juice off the shelf has preservatives in it and will not work well. Frozen or canned juices, (look at the label for preservatives) work the best..... or fresh is better yet. If fresh, you will need to kill back the wild yeasts with the addition of a camden tablet. Crush the tablet to powder, and add one per gallon of freah fruits, grapes or juices. Don't pour boiling hot water in on the fruit, as you can set the pectin in the fruits that have pectin, but hotwater with about two pounds of sugar is close to the right mix on everything.Disolve the sugar, then add your other ingrediants,yeast nutrient, acid (if needed), tannin, then the fruit or juice, and let set covered overnight before you pitch the yeast. Use a good winemakers yeast, that way you can get the same taste from batch to batch, and keep records. That's how you learn.

I keep the lid on and have never considered otherwise. I use a 5 gallon food grade bucket and the lid has a rubber oring seal. I use bung with an air lock. I fill the air lock with vodka instead of water. Let her get done rumbling before you go into the secondary.

Actually, everthing you can find on the subject will tell you to let oxygen in, in the primary. The yeast need O2 to reproduce and get going. I usually whip the mixture to a foamy mess when starting, after pitching the yeast. You get a quicker start, and less apt for a stuck fermation. The yeast are most vulnerable to being taken over by wild yeasts, right after they have been pitched, so a quick start is kinda important!

I've been hydrating the wine yeast in a few oz of 100* water and let it sit for 20 minutes before adding it to the must. I mix the frozen concentrate with water that's about 85*, then pour in the yeast mixture and some yeast nutrient. That seems to get it started real good and now I'm going to just cover it with cheese cloth.

Up to now I'm doing everything in gallon jugs. Chik Fil A sells tea and lemonade in some really nice clear plastic gallon jugs that I like because I can easily see what's going on in there. I'm fixin' to graduate up to a 6.5 gallon carboy. Sure would be nice to have a cellar about now!

This is what I use also. I tried once without airlocks and the wine oxidised and went bad before bottling.
Midwest brewery supply has a full wine kit that has everything you need and instructions. Would recommend highly getting a kit especially for the hydrometer which allows precise measurement of sugar's.

Primary fermentation is what makes the alcohol. Yeasts consume the sugar: alcohol and carbon dioxide are the by-products. When the alcohol level starts to gets up high enough it kills the yeast and things slow down rapidly. The secondary stage is where you keep air out. This process takes months whereas primary only takes about a week or slightly more.

Good discussion. I've read alot of info and there's many differing opinions.

OK to use the cheese cloth for maybe five days.After that,,,use an airlock.Airlocks are pretty much all the same size,,but you can get the rubber air lock holder(rubber stopper with hole in the middle to put the air lock in ) in any size for gallon jugs size,,carboy size,,whatever you need.Put a little water in the air lock trap and it becomes a one way trap.

Lots of yeast spores in our air that you need to keep out of your fermenting wine.

Correct. There is over 3000 wild yeasts out there, any one of them will give your wine a different taste. That is why sanitation and killing the wild yeasts on any fruit or juice is so important. When I got out of high school and got married, we did the balloon on the jug thing, then I got my hands on some ripe gooseberrys. Made my first batch of real wine, cleared nicely, looked pretty and everyone just loved it. Was made off of wild yeastes, and could never duplicate it again. Tried for a number of years, and give up in disgust! About 25 years ago, I was working in KC, and drove by a wine shop. Stopped one afternoon after work, and it changed my life. The lady was more than helpful, and I stopped in often and spent quite a bit getting outfitted, and now only buy occasional supplies. Surely changed how my outcome came out after that!