I've read a few different things about gel batteries and equalizing. Some say you can and some say no. My gel batteries say charge/absorption/equalize 6.9 to 7.3 and float standby at 6.7 to 6.8. I know it mentions it but I'm hesitant . My charger says it can charge gel agm deep cycle and "standard" . Supposed to me a micro processor controlled charger. If the battery is agm I use agm setting .. if it is gel or deep cycle or "standard" I'm assuming is had separate setting for agm because of equalizing but even I've Seen different settings for agm saying equalizing is ok for some batteries. Not sure if the charger is doing anything funny when charging the gel in standard. I have 2 6v batteries in series so 14.6 o guess is wgat they are supposed to charge at? But I heard what sounded like rice crispies popping in milk .. although it was faint and I felt around the battery and noticed no increase in temperature . My charge got up to 14.4 volts when I noticed the noise. What us your opinion? The battery are deka denominator gel batteries and the charger is a Viking 4 amp charger from harbor freight that can charge both 6 and 4 volts agm and standard batteries. I notice my solsr charge controler in my charges the batteries to about 12.5 with the gel setting.. and that under charged it... the charge controler is also harbor freight ...