180g Tank Build - 11 mos. and counting.

I used 1 1/2" intake and output. As long as the intake is the same size or bigger than the output there will be no cavitation. What hole Are you trying to widen, picture would be helpful.

Going to replace my GEN X PCX40. I'm excited - I expect to see less power draw and more flow. So, the return hole in my sump is currently sized for a 1" return and now I need to enlarge it for a 2" return. I know there are many reeflo fans out there - what size return / bulkhead do you REALLY use? Any advice on how best to widen the hole? A 2.5" (or close) drill bit seems cost prohibitive.

I think the best question/answer is knowing what you are planning on using to enlarge the hole? I have enlarged holes using a router with the size hole I am trying to achieve first drilled with a hole saw bit in a piece of oak plywood used as a jig for the router. Of coarse if you have a CNC machine laying around you could use that as well. I have seen folks drill sumps using hole saw bits, but I don't recommend it. I think it's too prone to cracking.

I use 2" for my gravity drains and 1 1/2" for my returns. I also prefer threaded bulkheads as oppossed to the non-threaded slip style bulkheads. Additionally I use a Bulkhead strainer on my return (suction side of pump inside the sump) using a 2" bulkhead, however I reduce to 1 1/2" on the pressure side of the pump and leave the 2" on the suction side. I use the 2" bulkheads on my return to utilize the 2" strainer found here http://www.bulkreefsupply.com/plumbi...strainers.html. But if you're under 250 gallons, I think 1 1/2" is fine all around as Midnight suggested.

hey heres my opinion if its a acrylic sump i would go to lowes and pickup a lenox bimetal 3" hole saw with arbor this will set you back about 23$ then get a 2" bulkhead. then get a scrap piece of wood and drill a hole straight through it to use as a guide. center the wood over your 1.5" hole and clamp it down or get a brave soul to hold it run the drill backwards as you drill through the sump if you try to drill regularly it will keep locking up and you could crack it. go about 1/2 speed and dont apply too much pressure. once you make it through loosen the chuck and take the dit out through the other side of the wall. if you drill in reverse its as smooth as butter no worries. dont worry about the pilot bit in the center the guide will keep the bit from walking.

if you have a glass tank i would purchase a 3" aquarium hole saw from glass-holes .com and drill a completely new hole somewhere else in your return section and just plug your existing bulkhead. drilling glass isnt to bad either just follow the advide on glass holes website in regards to drilling glass.

if you dont believe the ease of using the holesaw backwards ill post a video of me doing it it really makes all the difference in the world.

i just drilled a sump i built and used the same method but i didnt know to run it backwards and i was thinking "idk if this is going to work, it keeps locking up" and i remembered something about running a saw blade backwards to avoid chipping paneling so i tried running the bit backwards boom! easy as pie

I widened a glass hole with a diamond coated sanding drum. Worked like a charm! I takes time though! Patience is key!

I also selected my reeflo dart/snapper hybrid for my NEW 180 haha

Thanks for all the suggestions!