Passport 3320 Gray tank labeling

[fukutomik]

First time out with our 3320 and I noticed that the shower was not draining properly. I went to go check the tank levels and there are two gray tanks 1 and 2. I am guessing that one is for the kitchen and one is for the bathroom but is the kitchen tank 1 and the bathroom tank 2? We have been using both the shower and kitchen sink but one reads 2/3 and the other as empty? I went outside to check the drain valves and the black was of course closed the next one back is Gray 1? And it was closed but the next me back was slightly open and when I closed it and then opened it again I noticed that it made a rushing sound and then the shower started draining.
Bathroom is gray 1?
Kitchen is gray 2?
Why is my shower not draining properly?
I can only guess that the air vent overhead me get be clogged preventing the "air over water"
Thanks in advance,
Craig

[robo]

Craig was the drain plug out of tub/shower. Also 2 tank. Gray(sink) water and black(toilet) water. The surge u heard was letting water in the cap area to fill it up get a bucket when u go to dump yur gonna have a mess

[agargano98]

The 3320 has 2 grey tanks, one for the bathroom and one for the kitchen. 70 gal total capacity

[agargano98]

On the panel grey 1 is the bathroom, grey 2 is the kitchen. The dump valves the fwd one is kitchen and the aft one is the bathroom. I also had an issue with the tub draining. I found i had to open both grey valves to get a full drain out

[robo]

Cool my 2013 only has 1grey cool they put in a seconfd tank what year did they start that? Do you also have more that 30 gal of fresh water?

[agargano98]

Not sure when they changed. Mine is a 2017. My capacities are
Fresh 43 gal
Black 38 gal
Grey 76 gal