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View Full Version : Where to drill?


dlshaw
09/13/2006, 12:58 AM
Hello everyone!

I'm looking at buying a 60L x 36W x 25H (~240gallon) reef tank. I'm curious where people think are the best places to drill holes for circulation and filtration and please explain why :)

I've been thinking to use 2 holes in the upper rear section of the tank. I see a lot of tanks come drilled on the bottom with over flows. I was worried that if the seal fails that my entire tank would empty so figured I'd play it safe and put the holes up top on the rear of the tank.

If there is a good thread or site that you could link me to to read detailed information about this topic please post it as well.

Thanks

boxfishpooalot
09/13/2006, 04:42 AM
I keep thinking that it would be nice to drill on the sides of the tank. But if i did the back, I would drill the top about 3" below the water level. And I would do in the middle.

If it was a bare bottom tank, id drill at the bottom on the back glass to add flow down there.

dlshaw
09/13/2006, 08:20 AM
This won't be a bare bottom tank :)

Shagsbeard
09/13/2006, 08:52 AM
A 240gal is a pretty nice sized tank... you should have a good idea of what it will look like when you're "finished" with it. I'd page through the archives of the "Tank of the Month" and see what form of overflow you find most appealing. Some go with a box with space below it. Some go with a column that spans the full hight of the tank. It's appearances only, so go with the one you prefer. In a 240, I'd go with two triangular overflows in the back corners, full heigh of the tank. You probably wouldn't even notice them if you looked at the tank.

I'd get a professional glass-person (glanzier?) to do the drilling, and a professional pipe-person (plumber?) to do the installation. Call me wasteful, but I'm just not that handy of a guy.

Randall_James
09/13/2006, 09:19 AM
As you are "Looking" to buy the tank, buy the tank pre-drilled.

Where ever you purchase the tank, they will already have a good idea of what/how and where to drill the holes for you. (if they do not seem to know, find someone else to get the tank from)

Besides the normal dual overflow that these tanks usually have, keep in mind that a closed loop for circulation is pretty efficient and not very visible in the tank. Flow rates are going to be seem pretty outrageous (20-50X tank volume) but if you are going to keeping any stoney corals, it is required.

Just let your tank supplier know what you are planning and they should have pretty good recommendations for you (you can always post what they say here)

Randall_James
09/13/2006, 09:27 AM
Oh yea since no one else did this in your other thread :)

[welcome]

MCary
09/13/2006, 09:38 AM
It also depends on where you are going to put it. Bulkheads leak, but have pressure on an upper flange so they're not going to fail and dump all their water on the floor. And even if they failed, they would only lose water to the level of the overflow box. There is really no great efficiency advantage to drilling the bottom. The main reason is that the plumbing can go directly into the stand. This makes it possible to put the tank closer to the wall. If that's a concern then you'll need to drill the bottom. If you don't want a deep overflow box, then you need to drill the back up higher. In order to silence the overflow you will have to build your silencer outside the tank.

Closed loop? That's a more indepth conversation.

Mike

Randall_James
09/13/2006, 10:24 AM
The reason I say "talk to the tank maker" is that trying to "Reinvent" is not the best idea for most people. "Tried and true" system design is much safer. Also most issues of noise and flow have already been dealt with.

As this tank is going to be 36" front to back and "inwall", plumbing can be concealed pretty easily.

Circulation is going to be an issue with the big front to back space (3') and so should be considered from the start.

I would speculate that some overhead plumbing is going to be needed (calfo manifold) to make sure water moves at the front of the tank.

This sounds like a really fun project anyway, wish I had room for one like this

dtbradly
09/13/2006, 10:33 AM
Are you wanting to put your overflow, closed loop, or return holes in the bottom?

In the event of a power outage.....
Well, your overflow drain hole will drain until the water level is below it in the overflow. So if the overflow doesnt drain fast enough and your overflow is half way full of water, then all of that water is going to the sump.

Closed lop is no big deal it puts back what it takes out.

I am not 100% sure about this, but your return holes might drain until the water level is below them. I am not sure if pumps will go in reverse to say when the power goes out. Someone please correct me if i am wrong.

These would be my only concerns.

dlshaw
09/13/2006, 10:40 AM
Is it better to get overflows (like the Megaflows I've seen on All-Glass tanks) or just get holes drilled for a closed loop?

Randall_James
09/13/2006, 12:55 PM
The overflows are only meant to feed the sump/refugium. Circulation requirements (5000 to 12000GPH for your tank) are handled by powerheads and/or closed loop systems.

The closed loop just removes the powerheads from the tank (heat gain, and appearance issues).

You need to fully research how you are going to move the water in this system. A combination of closed loop with penductors and a pair of Tunze streams might be a good option (although certainly not the cheapest) The closed loop pump is going to be an important choice.