hole placement

martym · #1 08-11-2005, 12:11 AM

I'm going to drill my tank for overflows. Which placement is better on the bottom with a Durso, or on the backside?
Here is my thougths. holes in the bottom, can the water in the lower part of the overflow actually go stale, because everything is taken from the top part of the overflow. With hole in the back, I could make the overflow box shallower, therefore have a complete turn over of water in the overflow, and the boxes would take up less room. Any comments, or suggestions?
Thank you
PS the tank is 135g 6' long

Invigor · #2 08-11-2005, 12:34 AM

I did my 105 in the back corner at the bottom. With 3000gph going thru the overflow, it's by no means stagnant.

My only advice, if you're looking to do high flow, do 2 smaller overflows instead of one large one

martym · #3 08-11-2005, 02:38 AM

Back corner at bottom, never thought of that. What size of output hole do you have to get 3000gph?

Invigor · #4 08-11-2005, 03:05 AM

2" piping with a durso. I'm using a dolphin ampmaster 3000 with 1.5" plumbing broken into 4 1" inlets to the tank

martym · #5 08-11-2005, 03:10 AM

Looks good. How did you drill the tank? hole saw or dremel? How thick is your glass?

Invigor · #6 08-11-2005, 03:18 AM

I took it to a local glass shop, the hole must've been about 3.5" to fit the bulkhead, I'd say the glass is about 3/8" thick..nothing a dremel could easily go through.

for the hole and the 2 pieces of "tinted" 5 mil glass, it was about $60, would've been about $50 without the tint.

martym · #7 08-11-2005, 03:27 AM

I now see what you ment by bottom back corner. That was one of the ways I was thinking. What I thought you ment was lower side at the back. Do you know what the different gph ratings are for the different sizes of bulkheads? (this sounds like a job for Beverly's links hahahaha. just kidding if you read this Beverly)

Invigor · #8 08-11-2005, 03:39 PM

hmm,it's quite different I think. Given the proper tuning of the durso I should be able to get about 3500gph, it handles the flow of my pump full out, and I have very little plumbing so head pressure is at a minimum. I think a 1.5" bulkhead should handle about 2200gph, I don't remember where I picked that up, but I remember reading it somewhere. The difference is quite substantial when you get into larger plumbing.

mark · #9 08-13-2005, 04:04 AM

Had been considering a backside drilled tank (actually my case would have been side drilled) with full width horizontal overflow. Seems this would be an ideal configuration for skimming off the surface crud.

Invigor · #10 08-13-2005, 04:28 AM

Quote:

Originally Posted by mark

Had been considering a backside drilled tank (actually my case would have been side drilled) with full width horizontal overflow. Seems this would be an ideal configuration for skimming off the surface crud.

I really wanted to go that route, but the though of a glass box across the whole length of my tank kinda erked me away. If I were to build a tank I'd definately consider a coast to coast, but have it sorta external, and have the back pane of glass an inch shorter than the rest or something