Will two bulkheads alone work?

[ReefObsessor805]

I would like to drill my established acrylic aquarium to replace my overflow box. Will two 1 1/2" bulkheads, alone, work without an overflow box around them?

Input would be really appreciated. I would reallly like to replace my overflow box with some bulkheads on the back wall of my tank.

Without an overflow, will the creation of my bulkheads without "skimming" overflow boxes be a problem???

 

[Drue]

How are you gonna stop fish from getting sucked down the holes?

 

[ReefObsessor805]

I was thinking of a simple strainer.

 

[ReefObsessor805]

Anybody else have any input?

Is it necessary to have an overflow box around the bulkheads?

 

[GreenSarco]

It's always an advantage to have an overflow for the following reasons:

1. it will skim the water surface
2. you are less prone to losing flow because it won't get clogged
3. you won't suck up any fish or other animals
4. you might get a sucking sound depending on your water level
5. controlling the out flow may be difficult

For me to determine if two 1.5" bulkheads will work...

1. How big is your tank?
2. What size pump are you going to use to return the water?
3. How high are you placing the holes?

 

[ReefObsessor805]

My main tank is only a 46 gallon bowfront; my sump is 30 gallons.

My return pump is a Mag 3 w/ 3/4" PVC plumbing (~395 GPH)

I would like to put the bulkheads about 2" to 3" down from the top of my tank wall.

 

[Tang Salad]

I think you'll be missing out on the great benefit of removing the top layer of water. These bulkheads will take water out from below the surface, right?

 

[ReefObsessor805]

Unfortunately, yes.

I won't be able to build an overflow box around them.

I guess I am just going to have to upgrade to a larger CPR.

And then I can just run a closed loop on the back of the tank w/ like 3/4" PVC and 1" bulkheads.

 

[GreenSarco]

You could get away with 1-1" bulkhead if you wanted to. It will easily handle the Mag 3 pump. I would be cautious about how far you place the bulkhead...too low and you're sump with not be able to hold all of the volume...I would go around 1" below the surface...good luck.

 

[ReefObsessor805]

My sump can acutally hold about 4" of draining water from my main tank. My baffles are 13" and the sump is 18"...so my sump does hold a lot of extra water in the case of power failure.

My question is, say the bulkheads are about 1 1/2" to 2" down, will the water go over these openings?
I guess it will depend on my return pump's capabilities?

 

[JR719]

With a mag 3 and 2 1 1/2" bulkheads, you'll be lucky for the water level to be even half way on the bulkhead. Put the center of the bulkhead about where you want the water level. This is, if your drilling the back of the tank.

 

[ReefObsessor805]

Yea, that's what I was thinking.

I was thinking of just upgrading my CPR overflow, (there are some used ones w/ higher GPH ratings in the selling forum), so I can turn the ball-valve all the way on from my return Mag in my sump...

Then I can just do a sweet closed loop on the back of my tank.
If I'm going to drill, I might as well do that...I dunno. (Since I won't be upgrading tank sizes anytime soon)

 

[JR719]

Might as well. A closed loop would be a good addition. I've seen strainers for sale that just pop in the bulkhead and would keep fish out.

And just a rough estimate, a 1" overflow will do around 600 gph. I have a mag 7 and a 1" overflow. Only throttled back a tad.

 

[ReefObsessor805]

That sounds like an excellent idea.

Your closed loop has two bulkheads?
One going into the Mag and the other returning to the tank?

Or wait, haha, you just have a 1" overflow that is returned by your Mag 7...

 

[JR719]

Right, 1 return using the mag. For the closed loop, you definately want to drill that below the water line, I would say a couple inches to be safe. Don't want it sucking air and blowing bubbles all the time.

 

[ReefObsessor805]

Of course.

I guess I would then use 1" bulkheads w/ a 1 7/8" drilled hole sizes (looking at Marinedepot.com's plumbing parts for reference)
http://www.marinedepot.com/aquarium_plumbing_parts_fittings_bulkheads_strainers.asp

And use 1" PVC plumbing...
with a return Mag 7?

 

[JR719]

If your doing a closed loop, it will work fine. I am using it as a return and worked great. When I added a durso standpipe, I had to throttle the pump back a bit.

The bad is I had to throttle it down, the good, not noisy anymore. Now for a nice new install, a 1 1/2" bulkhead would be better fitted with a durso. Now that I think about it..... I may check to see if I have room to carve it out to fit a 1 1/2.

 

[ReefObsessor805]

The durso made it more quiet but slowed your overflow down?

Would I be able to put my closed loop pump on a wavemaker (RKII)? Or would the pump burn up, depending upon which pump, etc...?

 

[JR719]

Yes, the durso slowed down the flow just enough that I had to throttle the pump down a bit.

As far as a wavemaker, I really don't know how the RKII works. All I can say is I have a Neptune Aquacontroller and don't use wavemakers. My return is plumbed thru a seaswirl along with other ph's in the tank.

Your pump would be on all the time and would need some type of valves to open/close for wavemaking. I would think a on/off cycle close together would burn up your pump. But again, I really don't know. There is a gadget that some have that you plumb your return/closed loop line into, and it splits it up to 2 outlets that opens/closes so only 1 is open at a time. I just can't think of the name of it right now. That would work as a wavemaker and your pump would not have to cycle on and off.

 

[ReefObsessor805]

Yea. I'll just do a constant closed-loop, of course.

Should I use a Mag pump or some other kind of external pump?
Any preferences/reccomendations?