My friend, Rebecca, sent me this great tip:
One more thing, not sure if I told you this before but if the sponge tends to fall out of your aero drink system you can put a zip tie through your sponge and then thread it through the hole for the straw. It works pretty well since only 1 side of the sponge is attached so you can lift it out to clean it. I have lost that stupid yellow mesh thing so many times but the zip tie works wonders. I hope this makes sense.