If you have the room and do not need to transport look for surplus drums or totes. Leaks? Seal the threads with the same stuff you use to put metal water pipe together. Chlorine is almost a must have. Defiantly if you are treating surface water or nave the potential to get surface water into you drinking water. That said, if you go swimming you end up “drinking’ the water through your eyes and ears and it is hard not to swallow some. So, if you swim often, and the water has not changed, you should be ok. If you do not swim so as to get your body used to it best be careful. A friend from India says he has to condition himself to the local water when he goes home or he gets sick. Cl is preety cheap too. One gallon has the potential of treating over 3000 gallons of clear water. For storage you want about 5 to 10 PPM and around 2 for drinking. Slight odor, but your smeller may vary. Residual Cl means there are not pathogens in the water. One bottle of wine will treat 2 additional bottles of water. Looking for 3% alcohol content to kill the bugs. So mix beer 50 / 50 and sipp’n lik’er based on proof. Mix before you drink it! For 5.25% bleach, sodium hypochlorite use 2 to 3 drops per quart of clear water and let it sit for 2 to 4 hours depending on temperature. Adjust for the 8% strength or age of the bleach. Use the smell check as the bleach will break down into NaCl and water over time.Figure 20% a year. It treating a tank:One ounce is 590 dropsOne CC is a ml is 20 Drops so a syringe is a good measuring device.One oz is 29.6 ml Solid pool Cl stores a lot more Cl for the space but you need to be careful with the dose of have a test kit.Calcium hypochlorite works too. Figure the dosage as I do not have it. With clear water, in a clear container, and strong sun light, you will have potable water in one to two days depending on temperature, location and time of year. If you are storing water you need to know how to get more.You need some plastic sheeting to make a solar still then you can make water from the ground or recycle your water. If you have plenty of wood for a fire then look at a still made like a moonshine still.Use a 5 to 55 gallon metal container and some copper or even a garden hose to condense the steam to liquid. Two of the clear 5 gallon bubbler bottles will make a fine solar still. Examples on the net. If you have a well and the power is out. Pull the pump and get water with a weighted piece of PVC pipe lowered to the water level. Well depth is generally posted on the well. If the water table is shallow and above bed rock it is not hard to safely dig your own. I like to sink sections of 24 or 30 inch concrete pipe as I go as I really do not want a cave in and you need a liner any way! 30 inch is easier to work in but more dirt to remove. Easy to go deeper if the water table drops, just add a section and start digging!Biggest hazard is keeping the air moving but 4 inch drain hose and a small blower works fine. Point is – be ready before you need water.