Just finished my auto top off system.
I went the opposite route, using gravity to feed the system. I purchased a Kent Float Valve, a 5 gallon bucket, and a 1/4" push to connect fitting (push in x MPT). Drilled a 1/2" hole near the bottom of the bucket, put some epoxy on the fitting, placed in hole. Allowed to dry for 4 hours.
The hardest part about the entire installation was drilling the 5/8" hole through my acrylic Amiracle wet/dry/sump. If you ever want to drill acrylic remember... VERY slow and easy. It took me about 15 minutes to complete the hole. I would only drill for about 3-5 seconds and then pause for 30 seconds.
I ran 20' of 1/4" rigid air line tubing though the wall to my laundry room (lucky for me it's right behind my tank) where the 5 gallon bucket sits on the shelf above the washer/dryer.
Working perfectly! I'm so excited I don't have to manually top-off I don't know what to do with myself. It was becoming a every day chore! Total cost for my auto top-off setup was only $35 - All parts with the exception of the Kent Float Valve came from Lowes.
I also setup/installed my fuge. I copied JamesR's setup (Thanks James!!). I only went with one 3/4" bulkhead in mine though. I drilled a 1 1/2" hole for the bulkhead. I took a slightly different approach for pumping water into the fuge. I'm using a MaxiJet 400 (110
GPH) but instead of drilling a hole though the containers top I drilled a 3/4" hole just above the water line. Got a 90 degree 1/2" elbow fitting (barb x MPT). Got out the epoxy again and sealed it in.
I still need to cut the lid for the container and seal in a piece of plexi-glass for the light fixure. I'm going to order the same one, a Coralife Mini Aqualight.
All in all both of these project went very well, and were pretty easy. I'm very satisfied with the results of both project and really suggest to everyone the use of an auto top-off. There are several options available and it sure makes life easier, not to mention keeps your salinity at a more constant level.