First, as pointed out, T105 batteries are added in pairs to make a 12 V bank, and as such the voltage doubles but the amp-hours don't... so you're bank is considerably smaller than you're thinking.
Second, the voltage of the batteries is a surface charge that is not representative of their true state of charge. Read Maine Sail's post on voltage as a way to check state of charge—it doesn't work.
Third, what you really need, and it sounds like you don't have, is a battery monitor. This is one device that will pay for itself reltatively quickly, since it will show you whether you're actually undercharging your batteries, over-discharging them and prolong their life by allowing you to maintain them properly.
Also, you're making a really basic mistake in that the amp-hour capacity of the batteries isn't linear. It changes based the amp draw. The larger the amperage draw in relation to bank size, the lower the amp-hour capacity of the bank will be—this is due to the Peukert factor for the lead-acid batteries, and is the reason the FIVE-HOUR rate is so much lower than the TWENTY-HOUR rate when you look at battery specifications.
BTW, is the outback panel showing the AC amperage or the DC amperage. ONE AMP at 120 VAC is basically TEN AMPS at 12 VDC. I can't think of a 120 VAC ice-maker that would work at only .1 amp (12 watts)—freezing ice takes a lot of energy.
I'm sure my batteries are at the end of their life and I'm going to replace them but I have a couple of questions. Voltage and how it relates to stated Amp hrs.
I have a 12V house bank with 6 - 6 volt deep cycle batteries. Each Battery (Trojan T-105) is rated at 225 AH (20 hr Rate).
When I'm not at the dock I charge using a generator until the (Outback Inverter) meter reads 14.1 volts.
I shut off the gen and let it set and it drops to 12.3
I have a draw (again from the Outback panel) of one amp constant (Inverter is supplying a ice maker).
I also have a DC draw on my DC meter of < 5 amps.
After 6 hrs my voltage is down to 12.2 At 10 hrs it's down to 11.9
So, if I HAD 225 AH * 6 batteries I should have had 1350 AH (Assuming the 20 hr table) correct?
If I'm using 6 Amps (metered) and drew my batteries down to 50% would that mean that I should have been able to run the 6 amps for: 1350 AH total / 6 amps draw * 50% capacity level = 112 hrs?
If I replaced all the batteries with new, how would I calculate the total time it would take to bring the battery bank down to 12.1 volts assuming a 6 amp draw?