Drilling Return Line Holes

[Troy]

So my bulkheads have arrived and I have located a 1.5" drill bit (Rona) for anyone looking. Now, how far from the top of the glass and the corner should I drill the holes? I have .75' bulkheads and I plan on running 2 incoming returns on opposite sides of the tank to assist with circulation.

I have an older Miracles tank and the trim comes down at least 1" maybe even 1.5". Should I drill at the trim level or remove the trim and replace with new trim(its not coming off without breaking it, i tried).

 

[dale]

you would need to be at least 1/2" down from the trim for the flange around the bulkhead. im guessing you have an overflow box, the holes will need to be lower than the teeth so they are below your water level

 

[Matt1997]

Rona sells diamond hole saws?

 

[shamous113]

Rona sells diamond hole saws?

Yep, and home hardware.

 

[nanoreefwanabe]

There is no point drilling holes for returns IMHO... easier, safer and cleaner to have them return over the top... and you only need one return... your "flow" should be coming from circulation pumps (cheaper, more effective, more efficient)

As for drilling locations you need to be 1 diameter from any edge to any edge...ie if you have 1.5" bulkhead hole you need to be minimum 1.5" from the edge of the tank to the edge of the hole (centre 2.5" from edge) and you would want minimum 3" centre to centre between holes...

 

[TORX]

+1 to everything @nanoreefwanabe stated. I would suggest going over the top. When the power goes out, the water level drops significantly when you drill a return. A lot of people circumvent that by using LocLine and bringing the return up to the surface. That is a cautionary fix as just a bump with your hand or elbow will lower it and the results are a flood unless you sump is able to handle all that extra water. You can also move the over the top return if you want to switch its location. +1 to the single return as well, especially for just a 75 gallon with a corner overflow. Put the over the top return at the opposite corner of the overflow.

 

[Troy]

I was able to drill the hole decided on just one. It sits approx. 1.5 inches below the a water line. The water stops draining at approx. 1" below the water line. I added water to get eh cycle started and I am will be testing the capacity of my sump this weekend. To ensure that I have adequate room in the sump for the just in case power goes out. Based on my prior experience with this very issue, I have made sure my sump is large(r) enough, I just have to work with water level in the sump to set my ATO level accordingly. This to avoid having 75 plus gallon of water end up on the Library floor.

Side note, the "Wife Approved" test was required, when deciding on going through the glass. My first choice was over the glass.

 

[nanoreefwanabe]

Do your self a favor, test the sump by pulling the lock line out of the bulkhead... and then test again with the lock line pointing down... for that very reason that you can't be sure enough with a drilled return... and precisely why I will never have one again... over the top sitting on the trim, can never fall in, never have a leaky bulkhead, and never siphon more then a quarter inch...