I have one of those sterilite plastic bins with a lid, and within that a few a little plastic baskets, one for juices (which is now very full!), another for batteries, drip tips, new cartos, tanks, etc. Then I also got one of those 7 Day pill boxes at walgreens...the one that just has one slot for every day...cartos fit perfectly in them! I'm able to get 3-6 cartos in each slot, depending on which size they are. That's where I put any cartos that have juice in them, or ones that I have already used. It fits perfectly on top of one of the baskets, and is the same lenght, so somehow the millions of things in the Sterlite container is actually pretty organized!