DIY trickle filter questions

[Sicklid]

Okay, so I am full of questions here... tank is glass 55 gallon, looking to make a wet/dry full of bio-media out of a 5 gallon bucket, no sump, just several inches of water in the bottom of the bucket.

1) How close to the top of the tank can a hole be drilled for a bulkhead? I am looking at like 1" from the top edge of the hole to the top of the tanks' inside plastic black lip... There is more glass under that plastic, I am guessing another 1/2"? Hole diameter will be about 1 5/8" for a 3/4" bulkhead fitting.

2) Is a 3/4" bulkhead fitting large enough to make an overflow drain with a 1" to 3/4" reducing 90 elbow with notches pointing up to skim the top of the water?

3) If it is big enough (it's only for a filter, not a big sump) then what flow rate/size pump should I get for the return, and is there a bulkhead fitting that can go on the curved wall of the bucket for the external pump? Or should I raise the bucket a bit and have a bulkhead coming out of the bottom with a short internal standpipe inside the bucket? I am thinking about an Eheim external pump as they have an adjustable flow rate to fine tune this contraption, and also in the future, I will be putting a sump on this system. These pumps have a 1/2" inlet and outlet.

4) Does the height of the outlet on the bucket wall (if I can indeed put it there) make a difference as to the water level inside the bucket, as it's my understanding the last bit of bio-media should be somewhat underwater.

Thanks in advance from all of you pro's.

[czcz]

Not an expert and only had a rinky-dink wet/dry, but:

1) I'm not sure how close you can get, but fwiw my bulkhead on a much smaller tank (8gal) is ~1/4" from the top trim and ~1" from the side trim.

2) I think so. This will be noisy by the way as air gets sucked into the line.

3) Per RC's drain diameter calc, you should be able to move 300gph with the return pump (after head loss) alright. Little less for saftey/redundancy would be wise, of course. http://reefcentral.com/calc/drain.ph...0&drain=Submit

No help with the bulkhead fitting on a round container. How about a square bucket?

4) I don't think it will affect the water line. A submersed pump halfway or at the bottom of the tank keeps the same water line (after accounting for etc variables), for example.

HTH

[Sicklid]

Thanx CZ, I am scrapping the elbow and going with an inside overflow chamber built around the bulkhead instead, shoulda thought of that sooner... helps to move the drain hole further from the top edge that way too, maybe this will help noise reduction? And I am going to flatten/deform a portion of the bucket wall with my heat gun large enough for the outlet bulkhead there.

[czcz]

I think the chamber will be quieter, provided the water doesn't fall/splash too far. I'm sure this will be easier than it sounds.

Great ideas.