Cleaning your hydration pack!

Got some black deposits in the tube of your Camelbak? Dark stuff in the seams? Little black spots? You've got fungus, mold, and bacterial slime inside your hydration pack. Do you really want to drink that stuff? Didn't think so.

Cleaning the inside of the hydration bladder.
Cleaning the inside of the hydration bladder.
First, get the inside of the bladder clean. That's the easy part. You can use a baby-bottle brush. I've found what works best is a long-handled foam paint brush. The point of the foam gets into the seams nicely.

Use a little soap if you need to. But rinse thoroughly and let the bladder "soak" with clean water for a while, unless you want to taste soap for the next month. Just use plain water for your routine cleanings. Scrub into the seams, and don't forget to clean inside the port where the hose attaches. (A persistent nasty taste can mean the plastic is degenerating and poisoning you. If an odd taste persists after soaking the bladder overnight in bicarbonate solution -- 1 teaspoon per pint -- buy a replacement.)

Denture cleaning tablets can freshen the pack.
Denture cleaning tablets can freshen the pack.
If you can't get a brush to a cruddy seam area, squeeze the bladder sideways so the seam touches a flat area. Trap the seam between thumb and finger as shown. Now squish back and forth, working down the seam. Not as good as a brush, but better than nothing.

From time to time, use effervescent denture-cleaning tablets in the hydration-pack bladder. This does a good job of cleaning and removing germ bio-membrane deposits. Put 2 or 3 slow-acting tablets (such as Efferdent) in the hydration pack with cold water. Flip the pack every 5 minutes for 20 minutes. Let some of the fizzy mixture flow down into the tube as you do so. Let the mixture sit in the pack overnight, then rinse it out and let it air dry.

Hot water to kill any remaining spores.
Hot water to kill any remaining spores.
For deeper cleaning of stubborn deposits, use a paste of sodium bicarbonate baking soda (add just enough water to make it squishy) as an abrasive to remove stubborn deposits. The bicarbonate also kills germs and removes unusual tastes such as that "stale plastic" flavor.

After cleaning a slimy "gross-out" hydration pack, sterilize the bladder. This slows down the regrowth of spores and germs. Put about 1/2 cup of water in the bladder and toss it in the microwave. Don't boil the water! Just heat it up, a bit at a time, until the bladder is too hot to touch. Take it out and let it sit flat, so the hot water contacts the entire inside of the bladder. Leave it until the water is cool.

Cleaning the hose -- when you don't have a commercial hose brush.
Cleaning the hose -- when you don't have a commercial hose brush.
Now the fun part -- the hose. Pull the hose off the bladder, and pull the bite valve off the hose. I recommend you buy a tube-cleaning brush. That's a long stiff cable with a little brush on one end, made just to clean the inside of hydration bladder tubes. That's the best solution for a frequent rider. Quick and effective, with a tool made specifically for the job.

But if you're cheap or only plan to clean the tube on rare occasions, here's a home-made tube cleaner: Get an old derailleur cable. (Clean it first with soap and water if it's greasy!) Slide the derailleur cable through the hose.

Wrapping a bit of paper towel around the cable.
Wrapping a bit of paper towel around the cable.
Take a short piece of paper towel (NOT tissue paper). Get it slightly wet, then wrap it around the derailleur cable.
Insert your "cleaning kit" into the tube.
Insert your "cleaning kit" into the tube.
Spiral the paper towel a couple of inches up the cable, making sure it's narrow enough to fit into the tube opening.Slide the cable, with its paper towel coating, into the tube. (Don't pull on the tube yet.)
Once the wire is entirely inside the tube, pull!
Once the wire is entirely inside the tube, pull!
It may help to rotate as you push the paper towel-covered cable into the tube.Once the knob is inside the tube, squish the tube with your fingers, just in front of the paper towel. Pull on the free end of the derailleur cable. The knob will compact the paper, expanding it so it tightly fills the tube. Now we're ready to clean!
Passing your "cleaning plug" through the tube, while working on a problem area.
Passing your "cleaning plug" through the tube, while working on a problem area.
Slowly pull the cable through the tube. As you come to obvious problem areas, again squish the tube somewhat, so the paper rubs hard against the inside of the tube.
This paper used to be white. That's stuff you were drinking!
This paper used to be white. That's stuff you were drinking!
Once the cable comes out the other end, suppress your urge to hurl as you see what you've been drinking recently. Discard the paper. Reinsert the cable, get a fresh piece of paper towel, and repeat the process until the paper comes out clean and your Camelbak tube looks crystal-clean.

Now put everything back together.

Prevention!

If you're a water drinker, you can avoid fungus and calcium deposits by always using demineralized or distilled water. If you use a calorie-containing electrolyte solution, you're going to get critters growing in your hydration pack no matter how carefully you rinse it after each use. I suggest you buy a commercial cleaning kit. But if you want to go cheap, grab an old derailleur cable and a foam paintbrush, and make them part of your bike tool kit.

One way of slowing the growth of mold is to let the hydration pack sit for a day with a very dilute bleach solution (a teaspoon in an entire bladder of water). Rinse well afterward. This will inhibit growth of slime for a couple of months -- about the same time it takes before you stop tasting Clorox. I've done this, and it does prevent growth of algae and bacterial bio-membranes. But my kids complained mightily about the taste of the water. Also, the bleach will oxidize the plastic, reducing the lifetime of your hydration pack innards. Routine cleaning -- every time you come back from a ride -- is your best option.