The Planted Tank Forum banner

1 - 16 of 16 Posts

·
Registered
Joined
·
774 Posts
Discussion Starter · #1 ·
The reef company that building my new tank, suggested I go with 4 returns drilled up from the bottom of the tank. This would give me lots of flow. The tank will have one overflow box internal in the center of the tank, which will be for herbie type overflow.

I don't have room behind the tank to really bring the returns over the top nor do I want to.

My question is what happens when the power goes out to those 4 returns, won't they flood my sump or will they need to have some type of major PVC check valve?

Thanks
 

·
Pixel Prestidigitator
Joined
·
4,343 Posts
My bottom drilled 75 has a 1/2 pvc up to the top. I can't imagine they'd put the return under water.
 

·
Registered
Joined
·
774 Posts
Discussion Starter · #4 ·
if the return is under the water line by more then a few inches then you need a check valve. better safe then sorry with a huge mess to clean up. tank water is no bueno on the carpet. I know from experience.
My understanding is 4 returns will come up from the bottom, then they will be all tied together under the tank with check valve, still makes me a bit uneasy, if that check valve were to fail, 200+ gallons of water on the floor.
 

·
Registered
Joined
·
242 Posts
Fishstix - do you have room on top of the tank for a small surge tank? I you have the top framed all the way to the ceiling then its possible to put a 10-20 gal surge tank. This is a better way to return high rates of flow to your tank in a fail-safe manner. I will post some drawings if you want.
 

·
Registered
Joined
·
774 Posts
Discussion Starter · #8 ·
Fishstix - do you have room on top of the tank for a small surge tank? I you have the top framed all the way to the ceiling then its possible to put a 10-20 gal surge tank. This is a better way to return high rates of flow to your tank in a fail-safe manner. I will post some drawings if you want.

The tank is going to be 84x24x24. I don't have enough room in the location I am going to put it to leave it out from the wall so I cannot do bean animal and retuns on the back like I wanted to.

So I am going to have one center overflow put in with herbie style drain. Then it was suggested to have the return drilled up from the bottom of the tank. Not fan of that idea. Could I do something like the attached picture, and have him drill the returns into the overflow box? I would have primary drain/backup drain and then the 2 returns in the overflow box. This way I could drill small hole for the flow to break? Open to any ideas.

I don't have room for it to go on top as celling is 30 feet high.
 

Attachments

·
Registered
Joined
·
144 Posts
If it were me, I wouldn't want any holes in the bottom of a tank (especially a large tank) unless it was in the overflow box. It's just too much of a risk if you ever had a leak. As an added bonus, a leak back there could be a PITA to access at all. Could they drill the holes through the back glass? Just have plumbing up the back of the tank and a 90degree elbow in through the back glass?

Or going up through the overflow box like you have listed. Although you also may not want to have a whole series of holes in the bottom of a tank with the water pressure on it. The bottom giving out on a 210 would not be a fun time. Just some things to think about.

Why are you looking for 4 returns? Is that easier or somehow more efficient than having one or two return lines coming up and having it split once it is back into the tank?
 

·
Registered
Joined
·
7 Posts
Why not just install a second check valve in the two returns? It will cut your flow down, but will help to eliminate the possibility of a double failure.
 

·
Registered
Joined
·
774 Posts
Discussion Starter · #11 ·
If it were me, I wouldn't want any holes in the bottom of a tank (especially a large tank) unless it was in the overflow box. It's just too much of a risk if you ever had a leak. As an added bonus, a leak back there could be a PITA to access at all. Could they drill the holes through the back glass? Just have plumbing up the back of the tank and a 90degree elbow in through the back glass?

Or going up through the overflow box like you have listed. Although you also may not want to have a whole series of holes in the bottom of a tank with the water pressure on it. The bottom giving out on a 210 would not be a fun time. Just some things to think about.

Why are you looking for 4 returns? Is that easier or somehow more efficient than having one or two return lines coming up and having it split once it is back into the tank?
Thanks for the reply, at this point, and reading a lot, these guys might put returns in all the time on bottom, just scares me to much. I think I am going to go with returns in the overflow box. I think that the best way forward.

I was going to just do one box for the tank in the center, like above picture. 2 retuns, and primary and backup drain, total of 4 holes. Do you think that would work.
 

·
Registered
Joined
·
144 Posts
I'm not real experienced with it, just from reading on reefing forums. But I think it would work as long as the holes are spaced out properly so the glass isn't compromised. Presumably the company knows how to do that. Just looked like a crap-ton of holes in the above picture, but only 4 holes in the overflow should be fine. 8 fairly large holes in a row would be a bit concerning if it were in my living room.

My thought with returns on the bottom (not in an overflow) is the amount of water pressure on the bulkhead and seal, and the extreme difficulty in fixing the situation if you should develop a leak. Let alone a catastrophic failure (cracked bulkhead gives way, etc). Inside the overflow box, there is only the pressure of the water that's actually in the box, not from the other 200g of water.
 

·
Pixel Prestidigitator
Joined
·
4,343 Posts
I wouldn't worry at all about the holes in the bottom. My 75 has one 1.5 and three 1/2 bulkheads in the bottom. The pipes just come up to the surface from the bottom. My 90 is also bottom drilled but has the acrylic around it for the overflow. Needless worrying imo
 

·
Registered
Joined
·
774 Posts
Discussion Starter · #14 ·
I wouldn't worry at all about the holes in the bottom. My 75 has one 1.5 and three 1/2 bulkheads in the bottom. The pipes just come up to the surface from the bottom. My 90 is also bottom drilled but has the acrylic around it for the overflow. Needless worrying imo
So they run to top of tank? Do you run sump and pictures? They told me it would need it own pump closed loop.


Sent from my SPH-D710 using Tapatalk
 

·
Registered
Joined
·
1,846 Posts
Personally, I would not drill the tank for the returns. The slightest problem, and you will need to drain the tank to repair it. You get a leak, a bulkhead need resealing, a check valve needs to be replaced, and you have a major job on your hands.

With a return, yes , you can have similar issue if you don't use an overflow, but with an overflow, you can usually just drain the tank a little to make the repair.

I'm not a big fan of check valves. They always seem to fail when you need them. Over time you get some build up and other gunk, so if the water flow stops, they may not close. Then you got a flood.

I much prefer to run the return over the top rim, and drill siphon break holes just below the water line. Since there are no moving parts, they are much less likely to fail. Also the siphon break hole is a lot easier to clean. Just run a brush through them. A check valve needs to be taken apart to clean it. So if you drilled the tank, you either need to drain the tank, or install valves, so you can isolate the check valve and remove it for cleaning.

Granted, going over the top rim and down to where you want the flow doesn't look as pretty, but it's a lot less problems. Yea, I've done this both ways, and speak from experience.

BTW, you can get PVC pipe and fittings in gray or black, which goes a long way to hiding the returns and drains.

Another alternative would be to just have 1 or two returns an add some circulation pumps inside the tank. Much harder to hide those.
 

·
Pixel Prestidigitator
Joined
·
4,343 Posts
So they run to top of tank? Do you run sump and pictures? They told me it would need it own pump closed loop.


Sent from my SPH-D710 using Tapatalk
I've got a 1.5" and a 1/2" bulkhead on the bottom. Respective pipe runs to the top of the tank. I added a 3" adapter on the overflow after seeing it on some runs at a LFS. Right now I am only running HOBs on it. It's in my fish house. The sump I have for it is huge and I don't care for it. I've got another sump on a 22 breeder that I may transfer over. As it stands right now there is a piece of flex pvc sitting in the 40B below the 75from the overflow. The input side has a piece of 1/2" pvc that is right above the 40B. I had the sump running for a while then just disconnected it and left the pipe and tubing. When I do a WC I just let it overflow right into the 40B since it has plants in it. Hell the 3" adapter isn't even glued on and the connection is below water level with no leaks.
 
1 - 16 of 16 Posts
Top