I'm back home for the holidays and I'm helping my brother and my mum set up a 10-gallon tank I left behind. Right not I'm in the midst of a MAJOR disinfection (my little bro tried to keep a fish a few weeks ago and it died in just one night!).

I told him to just unplug everything except for the filter and I'd handle it when I got home. As I was taking everything apart, I noticed that the portion of the airline tubing that was left in the water had turned completely white. What could cause this? I immediately thought hard water, but my mum had a water softener installed quite a while ago.

Has anyone experienced this before? Should I replace the tubing?

This actually happens to all of my air tubing. I'm not sure what causes it though, but I just left it in my tank for now because I see nothing going wrong with it. But I think the white part is also a bit stiffer than the non white part. I'm not sure if its safe or not so maybe wait until someone with more experience replies.

I've experienced this as well. When it got to the point where I couldn't take it anymore I just bought new tubing. It's cheap and looks better than the white. I wouldn't worry about it. I never had the problem with well water, but with city water it has started happening.

you could always buy silicon tubing..and not plastic.
they last ages too.

i have silicone tubing in one of my tank, although it didnt turn any color, it was rock tho. it was no where near as flexible as it originally was.

In this case, I don't really need it to be flexible, it just leads straight down to a bubble wand.

I just hope it doesn't cause any damage to the fish.

I think that the tubing turns white (opaque, actually) as the plastic absorbs water. No biggie. Ignore it.

Dennis

The clear plastic suction cups and clear plastic tubing commonly sold for fish tanks contains a fair amount of plasticizers - chemicals that keep the substance flexible and soft. Immersing the plastics in water will eventally cause the plasticizers to leach out of the tubes/cups causing them to become hard - not "plastic". They also become opaque - white - when this happens.

There is no harm to your tank - the tubes will work just fine (the suction cups not so much). In fact - they are better than before because all the plasticizers are gone now.