new 800 AGM Batt. 09/21, ignored for 19 months. Put on monthly chg. program after de-sulfating with Romondes charger I got. It brought it from 90% to 100% in about 20 minutes. NOW (2 & 3/4 years later) it takes 3 hours to go from 90% to 100%. What I'm thinking is maybe another de-sulfating session ? Would I be jumping the gun ? Is this normal ? would anybody with experience care to expound on my situation ? Somebody with electrical wisdom cast an attitude on me ! Thanks, Stu