Over flow shaft and water level

[TokenReefer]

sorta. after a few days or week+ you may need to adjust. Seems to be based on evap/sump level and I've always thought that air pressure changes can affect it as well. Don' t know if I'm making that up or I read it some where.

Oh, how much water are we talking in the sump? I was under the impression it was filling up almost but I may have misread...wouldn't be the first time lol

 

[Joko]

Oh, how much water are we talking in the sump? I was under the impression it was filling up almost but I may have misread...wouldn't be the first time lol

120 Liter / 31,7Gallons

 

[SteveMM62Reef]

Is the Drain a Durso? You need a Hole Drilled in the Cap, on a Durso to Provide an Air Vent. Progressively Drill the hole larger, till the Durso is at a low noise level, that is best. I used a Counter Sink Bit and made a Very Slight, Smooth Camfer, to slow Salt Clogging, on the inside of the cap. I would raise your level in the Overflow Box, it needs to be just below your Weir Teeth, for noise reduction. Personally I’d get rid of the Emergency Drain, and install two Durso’s. Just make sure the inlets are at the same levels. This is part you are not going to like, your Drain pipes to the lower level are not big enough, and you are air bounding them. I saw this on Cooling Towers with Dry Sumps, and the Sumps were several storie(s) below, and inside the building. The pipe would be Engineered to a larger size, depending on the length of the run and how many 90,s there were. Also all the 90’s need to be Long Radius.

 

[FSP]

If the water level in the overflow box is lowering, then the siphon is draining faster than the pump is pumping. Either the pump needs to pump more water, or you need to restrict the gate valve on the siphon more.

A potential problem is that the "emergency" (an "open channel" or "Durso" in this usage) looks rather small compared to the other pipes. If the others are 40mm and 32mm, is the "emergency" 25mm? The "emergency" drain can be fickle if you're trying to feed it the minimum necessary, so try feeding it more water (either more pump or more valve as mentioned before). It will be noisier, as 25mm/1" can't handle much flow quietly, but it's in the basement anyway.

You may also be adjusting the valve too soon. Horizontal sections of pipe can trap air for a bit, so you might want to let it run 15-30 minutes at startup before adjusting. The pipe should not terminate more than 25mm/1" below the water level in the sump for the same reason. If you're really having a hard time purging the air and your sump has enough room for the extra water, you can consider lowering the siphon even more to allow more pressure.

Another issue could be the size of the pipe relative to the flow rate. 40mm isn't huge, but a 4.5m/14.75' drop is. How many lph are you pumping? You generally don't want the valve on the siphon line more than half closed.

All of the above problems would technically be solvable by converting your siphon to a "Durso," running two "emergencies," but your flow would be very restricted compared to a siphon. This may or may not be an issue depending on the size of your tank.

 

[Joko]

Hello,

What do you think about this idea;

I currently have the following wiring:

Drain 40mm pipe
Inlet 32mm pipe
Emergency overflow 25mm pipe

I've also heard that if the drain piping is too big, you can have problems with air in the mixing. And to rule that out, I wanted to try the following:

My drain and my emergency overflow arrive at the same point in the filter tank, and so I have the opportunity to swap the whole thing
What if I swapped my drain with the emergency overflow?
It would then look like this: my drain would be a 25mm pipe at the moment, and an emergency overflow would then be a 40mm pipe.

Would be very grateful for your opinions

 

[Joko]

If the water level in the overflow box is lowering, then the siphon is draining faster than the pump is pumping. Either the pump needs to pump more water, or you need to restrict the gate valve on the siphon more.

A potential problem is that the "emergency" (an "open channel" or "Durso" in this usage) looks rather small compared to the other pipes. If the others are 40mm and 32mm, is the "emergency" 25mm? The "emergency" drain can be fickle if you're trying to feed it the minimum necessary, so try feeding it more water (either more pump or more valve as mentioned before). It will be noisier, as 25mm/1" can't handle much flow quietly, but it's in the basement anyway.

You may also be adjusting the valve too soon. Horizontal sections of pipe can trap air for a bit, so you might want to let it run 15-30 minutes at startup before adjusting. The pipe should not terminate more than 25mm/1" below the water level in the sump for the same reason. If you're really having a hard time purging the air and your sump has enough room for the extra water, you can consider lowering the siphon even more to allow more pressure.

Another issue could be the size of the pipe relative to the flow rate. 40mm isn't huge, but a 4.5m/14.75' drop is. How many lph are you pumping? You generally don't want the valve on the siphon line more than half closed.

All of the above problems would technically be solvable by converting your siphon to a "Durso," running two "emergencies," but your flow would be very restricted compared to a siphon. This may or may not be an issue depending on the size of your tank.

Hi
At the moment I'm pumping about 1800 liters an hour from the filter tank into the aquarium. The pump is currently running at 90% power
My aquarium has a net volume of 500 liters. Would it then be an idea to swap my 25mm emergency overflow with the 40mm outlet? So my outlet would then be 25mm and the emergency overflow 40mm
What do you think?

 

[Joko]

Is the Drain a Durso? You need a Hole Drilled in the Cap, on a Durso to Provide an Air Vent. Progressively Drill the hole larger, till the Durso is at a low noise level, that is best. I used a Counter Sink Bit and made a Very Slight, Smooth Camfer, to slow Salt Clogging, on the inside of the cap. I would raise your level in the Overflow Box, it needs to be just below your Weir Teeth, for noise reduction. Personally I’d get rid of the Emergency Drain, and install two Durso’s. Just make sure the inlets are at the same levels. This is part you are not going to like, your Drain pipes to the lower level are not big enough, and you are air bounding them. I saw this on Cooling Towers with Dry Sumps, and the Sumps were several storie(s) below, and inside the building. The pipe would be Engineered to a larger size, depending on the length of the run and how many 90,s there were. Also all the 90’s need to be Long Radius.

My drain is not a Durso. It is a 40mm pipe which goes from the aquarium to the basement into the filter tank.

 

[FSP]

1800 lph is on the low end of even a 25mm siphon. Swapping the 25mm and 40mm pipes is fine, and the 40mm "emergency" will give you a lot more wiggle room.

That said, the 40mm pipe set up as a Durso should be able to handle 1800 lph as well, no problem. It will be a little noisier, but again, it's generally not a big issue with basement setups.

 

[Joko]

1800 lph is on the low end of even a 25mm siphon. Swapping the 25mm and 40mm pipes is fine, and the 40mm "emergency" will give you a lot more wiggle room.

That said, the 40mm pipe set up as a Durso should be able to handle 1800 lph as well, no problem. It will be a little noisier, but again, it's generally not a big issue with basement setups.

That means they mean that I will probably no longer have a problem with air in my drain? And the 25mm line manages my 1800 liters? Do I still have to install a shut-off valve in my 25mm piping? Where should the end of the piping be in the filter tank? Under the Water level or above the water level?
Many thanks

 

[FSP]

That means they mean that I will probably no longer have a problem with air in my drain?

Less likely. Drain systems really don't like horizontal pipe sections, but there should be enough velocity with 25mm pipe to purge the air eventually. Again, let it run for a while after start up before adjusting the valve, and make sure the pipe is low enough to allow ample pressure.

And the 25mm line manages my 1800 liters?

25mm at 4.5m can manage much, much more than that. Max theoretical flow is about 17000 lph, maybe 11000 lph actually when accounting for friction (extremely rough estimate, just an example).

Do I still have to install a shut-off valve in my 25mm piping?

Yes, you will have to restrict the valve a fair bit for 1800 lph.

Where should the end of the piping be in the filter tank? Under the Water level or above the water level?

~25mm underwater. More can trap air, above the water is noisy and splashes.

If swapping doesn't work, I'd just do the Durso thing on the 40mm pipe like others have mentioned. 1800 lph isn't much water at all, and it would absolutely fix your water level issues at the cost of some noise in the basement.

 

[Joko]

Less likely. Drain systems really don't like horizontal pipe sections, but there should be enough velocity with 25mm pipe to purge the air eventually. Again, let it run for a while after start up before adjusting the valve, and make sure the pipe is low enough to allow ample pressure.


25mm at 4.5m can manage much, much more than that. Max theoretical flow is about 17000 lph, maybe 11000 lph actually when accounting for friction (extremely rough estimate, just an example).


Yes, you will have to restrict the valve a fair bit for 1800 lph.


~25mm underwater. More can trap air, above the water is noisy and splashes.

If swapping doesn't work, I'd just do the Durso thing on the 40mm pipe like others have mentioned. 1800 lph isn't much water at all, and it would absolutely fix your water level issues at the cost of some noise in the basement.

Since it's in the basement, I'll try to leave the 25mn pipe above the water, because then the air can escape for sure. Noise in the basement isn't that bad
Thank you very much for the good explanations, and I'll let you know if it worked
Thanks

 

[FSP]

Hope it works out. Having the pipe above the water is also great for gas exchange