The battle continues

So I've been battling the evil cyno for about a year now.  I've covered the water, food, lights and flow.  After the addition of an ats the cyno has really  slowed down.  I still get some on the sand bed of my display.  Recently I have noticed the storage container for my ro has some slime on the walls. would this slime be contributing to my cyno?   I use a power head and a lid to ensure this wouldnt happen.  How would ro water  have nutrients to feed algae in the storage container?  Maybe the membrane is bad?  Why would it still test ok?  When I test at the source of my ro for nitrates I get zero.  What am I missing?  The algae in the ro storage is clear and can only be felt by hand.  Any input would be appreciated!  Thanks, Quam

 

Thanks for the link Foo. That sounds exactly like what I'm experiencing. I think I'll drain and scrub the ro container and then rinse with bleach. Thanks again, Quam