2012 Jay Flight 25RKS

[DEM]

I just purchased this camper used. From a search on the internet, the gray water and black water tank capacities differ from what I see underneath the trailer. The spec sheets say GW- 64 gals. and BW 32.5. On the tanks underneath the trailer a sticker on each tank give the dimensions as 24X60X8. This calculates to 11,520 cubic inches, at 231 cubic inches per gallon the tanks should hold 49.87 gals. 2 GW tanks and 1 BW tank. I'm happy for this additional capacity, just don't understand the differences.
An additional question; there is not a selector valve between the 2 propane bottles. I assume I should leave 1 bottle open until I run out then close it and open the other one.
Any input would be appreciated. Thanks.

[clubhouse]

My tanks are larger than the published specs too. I recall the specs said 32.5 gal for black and gray, but stamped on the tank was 38 gallons.

I handle my propane the exact way you describe. Leave one bottle open till it runs empty then open the other and fill the previous next time I get fuel.