65g Switchover

Since I have been talking about this so much recently, I thought I might as well start a thread for it. I am switching my 40g breeder to a 65g using the same home made stand and canopy. It was a very fun, long project over the summer until I got it finally setup and realized how awkward it looks. My canopy is at least the size of a 40g breeder so the whole setup was a little top heavy. So, now I have a 65g in progress to switch in place of the 40g.
Current residents in the 40g are two clowns and their Rose BTA, a Midas Blenny, Scooter Dragonette, and Coral Beauty along with my CUC. Lighting includes 2 150w MH with 20K Coralife Bulbs and 2 36w T5 Actinics. The tank (and the 65 to come) is drilled on the back wall which has PVC leading down to a 29g sump inside the stand. Also am running a BRS Dual GFO/Carbon reactor and hope to soon have a working skimmer.
Now on to my 65 I got it about a month ago and had four 1" holes drilled by Adam in the back wall. The 40g has a single drain but the new 65 will have two drains. The goal is to reduce the amount of surface buildup in the tank. I currently have a consistent filmy layer. A new skimmer may help with that also.
I would like everyone's input on how I should do the plumbing. I have gotten many suggestions for my drain but have come across a new dilemma. Due to how low we drilled my two drains, I have very limited height to work with piping before the drain has to turn into my stand and go to my sump. So, with this realization, I have made the two plans as follows:

The two outer holes are going to be my drains and the inner my returns. I am not concerned with my returns at this time but if anyone has any suggestions, I am all ears. The concern with my drain in both of these plans is circled in red. The two ideas are basically Plan 1- connect the two drains to have one larger sized pipe in my sump and Plan 2- leave the two drains separate. What I am concerned about is the horizonal portion of the piping. Will this significanlty cut the volume flow rate of my drain? Is it bad/less efficient to have a horizontal area in your drain piping or is this ok? Please let me know which Plan you think is better or if anyone has any other suggestions.
Other than this, Bill came over today and showed me how to redo the silicone. Thank you again Bill. Next step will be painting the back black. The week after christmas is when I'm going to start building my plumbing and I will be making the big switch on New Years Day... and I'm already getting nervous /DesktopModules/ActiveForums/themes/_default/emoticons/tongue.gif
Again, any input anyone has, please let me know. I hope the diagrams are clear enough for everyone. All I have is paint on my macbook so it's not very fancy but I'm happy with it /DesktopModules/ActiveForums/themes/_default/emoticons/smile.gif Thanks in advance!!!

 

Thanks for the suggestions! I was starting to lean towards two drain pipes. What do you mean exactly by an overflow? At this time both drains were going to have standpipes up to the water surface with a guard on each so my fish don't get sucked in. Is there something different you would recommend?

 

That does look nice. Would those work if my drains are halfway down the tank?

 

Thank you B-rad, thats the cover that I'm using now with one drain so hopefully with two drain pipes and a new skimmer I will be better off. I will definitely be doing two separate drains now. Always better safe than sorry /DesktopModules/ActiveForums/themes/_default//emoticons/smile.gif