bulkhead flow and noise problems

[jedheuer]

Hi,

I have drilled my 40g acrylic to take a 1" bulkhead. I have it plumbed through the tank to 1" vinyl tubing connected via a barbed 90 degree elbow.

The problem is that the flow fluctuates. Either it puts out to little flow to match my Rio 1100 return pump thus overflowing the tank or it the water backs up into the vinyl tubing, which creates enough pressure to start a siphon in the tank, and then it can pull enough water to match the return pump. This is way to loud though.

I don't really want to dial back the return pump because the rio 1100 doesn't really put out that much flow, but I cant really deal with the loud noise of the slurping bulk head.

I have the return hose below the water level in the sump. This seems to be the only way it will work. I cut the hose above the level in the sump and it would not drain nearly enough water.

Also I tried doing a T connection with one end open to allow air intake. This method severely reduced the flow through the bulkhead.

If anyone has any ideas on how to get a bulkhead quietly flowing full force please let me know. I would think that a 1" bulk head could match the flow of a Rio 1100 which is 382 gph.??

thanks

 

[Snausy]

Is the bulkhead in the bottom of the tank or the back?

I have two 1" bulkheads in the back of my tank for an Ehiem 1262(900gph) and it works great. Do you use an overflow to get the water in the bulkhead or is it exposed to the main tank with just a strainer without an overflow?

I have two lifereef overflow boxes(just the inside-the-tank part) siliconed and screwed to the bulkhead so the water goes from the surface to the overflow boxes then down the hole to the sump. I wonder if this could be the difference.

1" for 400gph should be fine. Although I'd be leary of not having any backup if something gets clogged.

If your bulkheads are in the bottom of the tank then this isn't applicable but if they are in the back of the tank you should use T fittings instead of elbows. The T with pipe extending up to the top of the tank(with a cap) enables you to control the amount of air introduced. When it's just closed up it will create that siphon and suck the water out too quickly for such a weak pump methinks.

Check this thread to get some ideas for tinkering:

http://www.reefcentral.com/forums/showthread.php?s=&threadid=1310585

 

[mfinn]

Where exactly did you drill the hole?

 

[jedheuer]

The hole is drilled on the left side of the back of the tank, opposite the return about 1/2" from the top of the tank and 6" from the side.

 

[Snausy]

1/2" from the top of the tank might be a problem imho. so obviously you are using a strainer and not an overflow box.

You COULD drill another hole lower and use the box...having your first hole as an emergency backup if the water level get's that high.

Just an idea.

 

[mfinn]

1/2" from the top is a small problem.
Maybe,,
a overflow box from a place like glass-holes.com, a down turned pvc 90 on the inside of the tank. On the outside, a pvc tee. On top of the tee, a short pvc pipe with a cap on top( hole in cap).
Kind of a modified durso.

Just a guess

 

[jedheuer]

Yes I am using a strainer, not an overflow box.


thanks for the ideas guys. I was trying to do away with the over flow box which I had before, hence the drilling. But the internal one with the bulk head might be a way to go.

Maybe its wishful thinking but it sounds quieter today, more like a bong instead of a broken toilet it did sound like the day before.

Anyways if there are any other ideas let me know.

 

[mfinn]

The overflow box to which I was referring to is the kind you silicone to the back of your tank that provides surface skimming in a drilled tank.