Karl wrote:
>I'd recommend a 20-30A Iota charger.

Fair enough.  This 30-amp model is not quite twice as expensive as my
8-amp ProSport:

http://www.amazon.com/exec/obidos/ASIN/B0074JVMUC/sbw/

I consider that a reasonable price for an important component of my
camper's systems.

>A 7- or 8-amp charger will never bring a battery that's been drained
>significantly back up at a proper rate. This can lead to sulfation
>on the plates, shortening the lifespan and/or storage capacity.

I looked on the Interstate web site and others for guidance on the
proper current for bulk mode charging of a deep-cycle battery.  I
haven't found anything clear and convincing.

I trust Karl's experience and knowledge.  I just wish I could find
some confirmation from a few more sources.

My 8-amp ProSport charger does get my battery up to the proper
voltage during the charge cycle, but the question is whether 8 amps
is enough to get the voltage up that high quickly enough to keep the
battery optimally healthy, especially when it's deeply discharged.

I've only charged the battery from down around 10.5 volts a couple of
times, and I didn't watch closely to see how long it took.  I'm
tempted to instrument the camper and record some data!

Anyway, I'd welcome some references to battery charging advice you
consider authoritative.