[kenmorton]

I seem to remember Norman saying someone had the tank collapse because the filler cap wasn't letting air in. Was this the Phantom supplied cap ?
Has anyone else had the same problem ?
What was the little work around that Phantom thought up ?
Reason I ask is I havn't had any problems because I have had a small leak in the top of one of my pipes but now thats fixed I don't want to flatten my tank.