Is there a such thing as over skimming in a reef tank? I just purchased a new recirculating skimmer from gerwin, and i have my other skimmer in my sump. Would it be beneficial to run both skimmer's? would it hurt anything to run both?

there is a respected author and coral farmer who recommends different kinds of skimming to better grab organics when possible and or budget allows.
Short answer, use everything you got if you have room and the inclination to do so

That is what i was hopeing you would say!

Everything I have read, Says, with an SPS tank, for maximum growth, you can't skim to much. For a soft coral tank or mainly soft coral tanks like Sandy's, who cares, you can't argue with her success and she has no skimmer. I am sure that Sandy's large zoa colony's eat alot of the particles that turn into nitrates in her tank. I have read from people that have SPS tanks, that have Nitrates that are in the 30 to 40 range and their tanks are doing good and have a decent growth rate, anything above that and their SPS corals are starting to die. The best SPS tanks that I have seen, the ones with the best growth rates, all have two things in common, monster skimmers and zero nitrates. I would say that, it all depends on the type of tank you have, soft coral tank = any ole skimmer SPS Tank = the best skimmer you can get. I don't know what type tank you have, but if its an SPS tank and you think you need to run two skimmers, I would just think about upgrading to a larger mo better skimmer, and keep the one you now have as a back up.

My skimmer is not agitating never much its brand new from Gerwin. i havent finished my sump yet so its not up and running but i was playing with it and hooked it up. it was tap water so ofcourse there was no foam but there was very lil bubbles i tried opening the air line more and still hardly any bubbles compared to what i have seen on line from other skimmers

1. Skimmers do not function properly in fresh water, I think its the ph but don't quote me on that.

2. The skimmer will need a break in period, usually a couple of weeks, before it will operate efficiently and consistently. Like everything in this hobby...it takes time.

is there any bubbles in it? everything phisher told you is correct you will not see the same level nor density nor fine bubbles but you should see some bubbles as air is still being sucked in. if that is not the case come by so we can see what you are doing wrong