ballast won't drain

I added a bow sac to my X-star (205V) by tying into the KGB sac pump as described in this thread:
http://www.wakeworld.com/MB/Discus/messages/3183/579077.html
The problem is I can't get the system to drain now. The pump will pump water in and out the overflow. I flip the drain switch and I can hear the pump reverse and it sounds like it is pumping out, but no water comes out. I do have the yellow impeller in the pump. I even tried squeezing the KGB sac to force water down the hose to the pump, but it wouldn't pump. I tried isolating the system with the valves too draining just either the bow or KGB by itself, but no luck. It worked fine the first time out, but hasn't worked since? Not sure what the issue could be. Any ideas?

Same issue a few weeks ago for me. Fuses on my boat are under the dash. At least 4 of em for the ballast bags. One was blown and it started empting.....after a few times, same issue port rear bag not emptying, fuse not blown this time but pulled them all and plugged them back in...started working again...stay tuned.

I went and replaced my yellow impeller with the original black one. For whatever reason that seemed to work. Was able to empty the bag here in the driveway now. The pump always ran and switched directions from fill to drain, just wouldn't drain? It does now though? I thought I read on here that the black impellers create a better suction or something like that?

the ballast on x stars never work...... never. brand new 80K off the floor....... ballast still has problems.