I made a similar posting on the Farcebook Albin 28TE page and a Gentleman pointed out that the remaining 10 gallons, for a total of 36, are in the HOT WATER TANK..
Duh, I stand corrected: In South Florida we never ever use the Hot Water Tank, it did not even cross my mind.
Yes of course we should use the aft deck shower only with the hot water.
(After it cools off and becomes lukewarm.)
My bad, I have owned and lived on numerous boats in the Caribbean and in South Florida, but none of these vessels had a Hot Water Tank.