battery set up for thrusters

[RJM100]

Hi I am installing a bow thruster and a stern thruster on a 45' power boat. there are two house battery banks with three paralleled batteries in each, each bank is rated at 1010 CCA. I was originally thinking of running the stern thruster off of one bank and the bow thruster off of the other bank but the side power thrusters spec a minimum CCA from the batteries at 1045 CCA for the bow thruster and minimum CCA for the stern thrusters at 1425. do I/can I parallel another battery onto each house bank to meet the minimum CCA that the thrusters need? does it have to be a deep cycle to match the house bank or can it be a high rated CCA cranking type? what effect will this have? I think a new bank of batteries would be the best option but the cost up front does not appeal to the boat owner. ....oh yeah and am I right to assume the CCA stamped on all these marine batteries is SAE standard, or is it DIN ?
Thanks -Robby

[rasorinc]

What about running both battery sets to an equalizer that will control the correct voltage to the thrusters. I can't think your discharge load would be very heavy just docking and undocking.