drilling project

[TheGuyFromNJ]

I am going to drill my tank this weekend and I came up with a neat idea and looking for some input. Here is my plan:

The red being to the sump. Standard design.

The blue being the return from the sump. What I would like to to is have this come into the back of the tank behind the rockwork about 2-3" from the bottom of the tank through a 1" bulkhead then attached to the middle of a 1/2" PVC pipe with little vent holes drilled into it running the length of the tank to act as a way of moving the water around behind the rock w/o actually putting a powerhead back there. My sump returns about 600gph max. The tank is 36" long 65gal.

What do you think? Where would I put the air vent to prevent back siphon? <br>

Thanks in advance for your help. Any suggestions are greatly appreciated.

(Sorry for the poor drawing.)

 

[MikeNapoli]

Not sure if it's fool proof. You would need to put a checkvalve on the return and still not sure if those things are 100% perfect. I've heard stories that those break. That could possibly drain your entire tank. Actually it will drain your entire tank.

Might be better if you put the spray bar across the top and aimed it downward behind the rock.

 

[TheGuyFromNJ]

I am trying to avoid any plumbing in view. Keeping the whole filtration system out of sight, thats my motivation.

I was thinking a check valve, but I dont know if I want to bet the whole 65gal of it in an apt. Thanks for the input.

 

[Phyl]

I'm sorry to say I don't see a way for this to work that will be fool-proof.

Check valve isn't going to solve your problems (long term) and there is no way to break that siphon. The way the back-siphon prevention hole works is that the water has to climb up and over the wall of the tank to get out (hence needing a siphon to allow water to escape). Placing a hole strategically allows you to stop that water from leaving the tank because once air gets in that hole, the water can't get up and over.

What your design essentially creates is a drain, not a siphon. There is no fool proof way of protecting that.

If you want your plumbing "out of sight", look at Dan's plumbing job with the internal overflow on the "unviewed" end of the tank.

 

[TheGuyFromNJ]

How about something like this:

Using the check valve just to prevent the water from going up but pulling air down when there is suction?

 

[Phyl]

If you ran that pipe out of the tank and then up to the top of the water level and then back down under the tank, apart from dealing with potenial water spay, you'd be ok. I'd guess that siphon hole would spray (and potentially clog, as can happen).

Still flirting with disaster.

 

[pgordemer]

The blue being the return from the sump. What I would like to to is have this come into the back of the tank behind the rockwork about 2-3" from the bottom of the tank through a 1" bulkhead then attached to the middle of a 1/2" PVC pipe with little vent holes drilled into it running the length of the tank to act as a way of moving the water around behind the rock

Becase the output is under water so far down, and along an extended, it would take very very powerful pump with lots of head pressure to get the water out. The depth here is working against you.

There is also no way to protect all of this from running back into the sump on shutdown.

 

[RichT]

Not trying to discourage you but that is a recipe for disaster IMO.

The only way a spray bar on the bottom is going to work is if the feed goes up and over the top of the tank with a little hole just below the surface of the water (until the hole clogs) and, like Phil mentioned, a pressure rated pump. The check valve in the second sketch will absolutely not work. Your creating a drain as others have said, not a siphon problem. A check valve between the pump and the spray bar would be the only way it will work (until the check valve fails) and again, a pressure pump will be necessary. I use a check valve in my return line only to keep the back rush from stirring up the detritus in the sumps return chamber, not to prevent floods.

Personally, I've never seen return lines installed any way other then over the top. The only other way I've seen returns drilled through the bottom of a tank is reef ready tanks which bring the return to the top up through the overflows.

Good Luck.

 

[TheGuyFromNJ]

thanks for the help. I guess it is back to the drawing board.

 

[shinningballs]

y not put both holes on top?

 

[TheGuyFromNJ]

y not put both holes on top?

I guess I am now

 

[TheGuyFromNJ]

well its drilled. Wasn't nearly as bad as I thought it was going to be with this old tank and the thick glass. Took about 10 min.

I used a 1" bulkhead and I have a 1" return. I thought that the drain would keep up with the return pump at full throttle, but I was wrong, maybe 1/2 throttle. I guess next week end I will be drilling another hole on the other side for another drain.

I am trying to get away from having any type of overflow box in the tank, but even with a make shift durso I am still getting noise.
my make shift durso is a tee with one leg as the overflow the other going above the water line with a pvc cap and a hole drilled for air

Here is a pic of where I am now: http://img125.imageshack.us/my.php?image=pict0004gp3.jpg (only the chromis wanted to say hi)

You can see my make shift durso in the right corner.



Always open to suggestions.