This information will tell you how to properly open, clean, cut down on algae growth, where and how to store them, how to siphon them, when to rotate, etc.
The first trick is to get one of the two 4-inch bung lids unscrewed. (NEW barrels have two screw-in lids, but some USED ones have one screw-in lid and one sealed metal cap. If you have one of these, leave the sealed metal cap on forever.) If you can’t get the plastic screw-in lid unscrewed with your fingers, take a pair of pliers and put the handles down in the X-shaped thing on the lid, pull the pliers open, and unscrew the lid by turning the pliers. The pliers give you leverage and something to hold onto. You can also buy bung wrenches made for just this purpose (if you have a poly bucket lid lifter, often times they will have two triangular 'knobs' on the side that are made to open the bung lids (as shown below - just below the 'u' shape).
If you purchased used barrels, they need to have the soda pop syrup rinsed out of them. YOU NEED TO WASH NEW ONES OUT TOO, but barrels that contained soda pop have a better chance of growing bacteria due to all of the sugar.
To Clean: Just put the squirter nozzle on your garden hose and squirt around in the barrels, add some soap, squirt some more, roll them around, then dump the water out, squirt some more, dump it out, etc. Repeat this process until you feel happy. It is also recommended that you then pour a half gallon of chlorine bleach into the empty barrel and roll it around some more and then let it stand for 2-4 hours with the bleach in it. Then dump out the bleach and RINSE IT OUT REALLY WELL. (This will cut down tremendously on future algae growth.) If you’re doing all this in the winter, just wait for a warm enough day. You can also clean out your barrels with the power nozzle at the local car wash!
Put the barrel(s) where you want them to be — if you are storing them on cement, put some newspaper, carpet, grocery sacks, wood, or whatever under them so the water won’t pick up a cement taste — and then fill them up with a food-safe plastic hose (available at RV supply stores - I even got mine at Wal-Mart for about $10). A regular garden hose is not recommended, but of course is better than nothing.
If you’re storing the barrels where they might freeze, be sure to LEAVE ABOUT 9” EMPTY AT THE TOP FOR FREEZE EXPANSION. You might be wondering what will happen if you need the water in the dead of winter and your barrels are frozen solid. That is unlikely, but the chance that they could freeze is another reason at least 2 methods of water storage is recommended.
It is recommended by almost everyone including City Water Depts. that you rotate your water storage annually. (try to leave 9” empty on top for winter freezing.) When you’re ready to rotate the water, first siphon out the old water with a garden hose, squirt the barrels out with a squirter nozzle several times, treat them with bleach again as described above (#2), rinse them again really well, and then fill the barrels with fresh water using a hose made specific for water. (Travel trailer and motor home stores carry them) If your hose water is cholrinated and you rotate your water annually, you shouldn’t need to add more Clorox. Sine people like to add liquid oxygen, but I have never tried it.
Changing the water once a year only takes a few minutes, because once you start a siphon with the hose, the barrel empties itself while you’re able to do other things.
5. Water Cleanliness:
It is important to know that even tap water has some bacteria in it, and so unless your containers and water are 100% purified when first storing, bacteria will multiply over time if exposed to light and heat. They will multiply even more if they have sugar to eat, which they do with if your barrels are used and any pop syrup remains in them. Do your best to sanitize all your containers and use the purest water possible for storing. Then if you think your water might not be safe enough to drink later, filter it, treat it, or purify it again before using.
6. New vs. Used:
The pop taste is very slight in most used barrels but lessens each time you rotate your water. Many used barrels are translucent white. Supposedly, NEW and BLUE barrels grow less algae. BE SURE YOUR BARRELS ARE MADE OF FOOD-GRADE PLASTIC and that used ones have only had something edible for people in them before. New barrels, although more expensive, might be safer since they have nothing in them for organisms to feed on. But again, anything is better than nothing!
7. How to start a siphon:
First, put a squirter nozzle on the end of your hose and then turn on the water. Squirt some water out through the nozzle until all the air is out of the hose and the hose is full of water. With the nozzle still screwed on the end of the hose but not spraying, turn off the water at the faucet end. (The nozzle on the end should be keeping the water in the hose.) Unscrew the hose from the faucet, stick your hand over that end of the hose, and hold that end up to keep the water from running out, and then put that end of the hose down into the barrel ALL THE WAY TO THE BOTTOM, and put something on top of the hose to keep it from pulling out of the barrel. Then run the rest of the hose along the ground (downhill if possible) and unscrew the squirter nozzle. As the water already in the hose runs out, it will start the siphon and empty out most of the water from the barrel.
Pumps/siphons are sold as well, which would of course be a better option if you were storing your water indoors.