I bought a new/used boat this and put new depthfinders on it. My problem is that once I get to a depth of about 15 feet, my console depthfinder makes my bow depthfinder useless. It sends crazy signals and eventually stalls.

Any advice?

Turn off the console unit.  Some of the newer graphs will filter out most of the interference but no unit will complete eleminate it without degrading it's signal.  Some will run a 200khz console and a 400khz bow to get around it.

Turn off the console unit. Some of the newer graphs will filter out most of the interference but no unit will complete eleminate it without degrading it's signal. Some will run a 200khz console and a 400khz bow to get around it.

In the past I've always had a "puck-type" transducer on my trolling motor and have never had a problem, now I have skimmers front and rear, could that be part of the problem?

No.  The only thing the X-ducer has to do with it is the angle of view.  The wider the angle they have the sooner they will pick up the other units signal.