Help...

[Bruce]

Yeah I was thinking that....my Mum won't like that though

Bruce

[BaZ]

An old one

All fishkeepers should have old towels on hand

[Bruce]

Very true, I actually do have an old tattered towel that I use. I'll use that. Would weirs be the best option?

Bruce

[BaZ]

Would weirs be the best option?

I really don't see how a weir could improve your situation over a standpipe which is the correct diameter to carry the volume of water.

Behind a weir, you normally have a standpipe anyway.

Let's break the basics down for a second:

-You should start with a tank that is full of water, and a sump which is filled to the correct level.

-You turn the pump on, and it moves some water from the sump to your tank.

-This means the tank is now filled above the level of your standpipe or weir, causing water to overflow and fall via gravity to your sump.

-The only water which enters your sump should be water which has already been displaced from it via the pump.

-It should be impossible for the water level in your tank to be below the level of your standpipe or weir, therefore you should not have too much water in your sump.

Common issues:

-Pump too big for the return plumbing. This will mean the water level in the tank will gradually get higher and your sump will empty and your pump will burn out. The solution for this is to use larger diameter plumbing back to your sump, or run a smaller pump.

-Gurgling or slurping noise coming from plumbing. There are a number of ways to fix this but for now lets concentrate on your more obvious issues.

Does the above make sense? Have I left anything out of it which might be causing you problems?

I'm still really puzzled as to how you are getting too much water into the sump. Is the water level falling below the level of the standpipes in your tank somehow?

[Ash]

He was making a siphon BaZ

[BaZ]

Are you sure? Look at the pics. Doesn't look like a syphon to me, I thought maybe the standpipes might have been sounding/acting like a syphon so he just called it that.

Maybe it's best if Bruce starts fresh and gives it to us straight with photographs and a clear description of what is happening to save us all guessing

[Bruce]

It is a siphon. I took the end bit of the pipe...the cross bar, end cap etc and dipped then under water to remove air and then put them on the pipe. There was no end cap either. When the water in the tank got too low from the siphon power it would start sucking in air and the thing would fail. I think I am defianately going to get some weirs going in. One in each corner...40mm piping. That should do the job.

Bruce

[BaZ]

Have you read all the stuff in this thread Bruce?

What makes you think you should get a syphon going?

What happens if you just start it off as per a normal standpipe/weir?

[Bruce]

I tried that but the thin pipes can't handle the 8000l/h and the tanks water level starts rising.

Would 40mm pipes in two weirs be adequate?

My 200th post btw

Bruce

[wui39]

That would mean you have the highest average post per day I think.

[Bruce]

Nothing wrong with being active. As long as it's all relevant.

Bruce

[BaZ]

I tried that but the thin pipes can't handle the 8000l/h and the tanks water level starts rising. 

Would 40mm pipes in two weirs be adequate?

My 200th post btw 

Bruce

←

Your options are to increase pipe size or decrease pump size. How many times per hour do you want to turn the tank over?

Otherwise I remember someone early in this thread suggested tapping the hose from your pump and returning part of the flow back to the sump. That is the same as decreasing pump size and gives you some time to work out whether you need to re-drill your tank.

200th post

I think almost half of those would be in this thread. Let's try to get all the info out first up in future. These issue could have been solved on the first page had it been clear to us all what the issue was

[wui39]

Come on Baz I know you love posting too! I know I do

[Bruce]

Ok, prepare yourselves for a long post. I am going to start from scratch and try and explain everything with pictures as well as I can. Here goes;

I cannot match the speed at which the filter outputs water and the standpipes take in water. The standpipes are 3/4" or 20mm in diameter (not my choice, 2nd hand tank). They have the options for a couple of things at the top of the standpipe. An open pipe, a durso style standpipe or a horizontal cross bar intake. The two pipes then flow down into the sump. They flow into an foam filled prefilter where the water spills over a glass divider onto the bioballs via glass diffusers. It then flows over another divider into the pump area where it is pumped back up into the main tank. Here are some pictures to help with your understanding;

Tank

Left side sump

Sump showing prefilter and overflow glass

Right hand pipe

As you can see the pipes for the setup are quite small compared to the large sized tank.

I have tried several options with the pipes involving different ways of intaking water. I have tried open top pipes, durso standpipes and horizontal bar intakes. Pictured here;

Durso Style

Horizontal bar intake

Open top pipe

Because of the pipes small diameter it doesn't work very well as overflow pipes as they are too thin. Because the pipes are too small the tank water level rises and the sump empties causing the pump to run dry. So to prevent this I take off the t-joint, prime it by submersing it underwater so that it has no air bubbles in. This of course causes a siphon effect which is too powerful and takes in too much water. The pipe is about 2cm underwater to have something there to siphon. It uses that water before the pump can replenish it. So the sump ends up filling with too much water until the siphon is broken by air entering it from the tank water level dropping. It then reverts back to the inadequate gravity method. Me and my dad tried to restrict the siphon flow rates by using the cross bars on the siphon but it is near impossible to perfectly balance the intake with the output which is why I want weirs. The weirs will have a bigger 40mm opening which should be plenty big for the pump.

I hope this huge post help to answer some of your questions.

Bruce

[wui39]

I think the first problem is that the pump is too big so you need to have T junction and a valve to regulate the flow, unless of course you want such a massive flow of water.

The sump may be overflowing because when you siphon the water down it has to flow up and over the glass divider. This causes the water to slow and therefore overflow.

Since you say the tank is 2nd hand the best person to talk to may be the guy/girl you bought the tank off. They should have some experience with what needs to be done. I know when I bought my tank the guy explained to me what was needed.

At the end of the day, and if you decide to go with the weirs it going to cost you extra. Probably all up including labour you would be looking at least another $100.

All of a sudden these 2nd hand tanks cost almost as much as new ones!!! lol

[Bruce]

I have and they told me what to do. I tried it with no luck. To be honest I don't think it was ever running. He said it was but then his wife came out and said he never had it running so I don't know really. All I know is that what he told me to do didn't work.

Bruce

[BaZ]

Wui is right.

Grab a T-junction and put that in the line from your pump back to the tank. Run some extra hose from this junction back into the sump, and put a tap on the end of it.

By adjusting that tap you can regulate how much water goes up to the tank, and by having the tap on the branch rather than the main line, you will never restrict or overload the pump.

Otherwise try a smaller pump (a bigger expense than the T-junction) or get the tank re-done to match the pump (the most expensive option).

You're welcome to come for a drive and see my sump and how it is set up, I use the T-junction method to regulate my water flow.

BTW thanks for the pics, they make it much easier to diagnose

The first pic shows just how narrow your standpipes really are for a tank of that size

[BaZ]

Also Bruce, did you buy the tank from a forum member?

If so, please PM me about it

[Bruce]

Although I could play around with taps etc. I would rather go for the weir option, IMO they are a lot less of an eyesore and the standpipes as seen are not display tank quality which is what this is. Does anyone know if Cyp. Leptosomas mind a lot of current?

Bruce

[jebe]

i have an idea on how you might be able to regulate your existing system, but it wont be pretty

On the end of you standpipes if you add a length of hose and loop it around i.e. one end on the standpipe and the other pointing to the bottom of the tank making a loop or two.

Use some cable ties to hold it in place.

(the loop from the hole in the hose to the tip pointing to the bottom will need to primed)

i will help you

You would then need to place a hole (good size) in the top of one of the loops the first piece of hose you would see as the water drained.

As the water rises above the loop sealing the hole> starting the siphon effect, as the water level drops below the loop exposing the hole> the siphon would stop

you could use this method as anouther way of getting water into the sump

It would be an on/off switch which would be controlled by the water level in the tank

Try it, it might work ?????

cheers justin

[Josh]

Bruce a weir wont fix your problem. Water will still be draining out the same size holes

Buy a smaller pump and it will all be sorted. Nice and easy

Josh

[BaZ]

i have an idea on how you might be able to regulate your existing system, but it wont be pretty

On the end of you standpipes if you add a length of hose and loop it around i.e. one end on the standpipe and the other pointing to the bottom of the tank making a loop or two.

Use some cable ties to hold it in place.

(the loop from the hole in the hose to the tip pointing to the bottom will need to primed)

i will help you

You would then need to place a hole (good size) in the top of one of the loops the first piece of hose you would see as the water drained.

As the water rises above the loop sealing the hole> starting the siphon effect, as the water level drops below the loop exposing the hole> the siphon would stop

you could use this method as anouther way of getting water into the sump

It would be an on/off switch which would be controlled by the water level in the tank

Try it, it might work ?????

cheers justin

←

I might have missed something here but I cannot see how this would get more water through the same sized holes

[Ash]

a siphon flows more than just gravity

Don't know all the technical reasons but for one in a gravity drain there's air in the pipe & in a siphon there isnt.

I know draining my tanks (for waterchanges) with a siphon with a 25mm ID hose drops the level way faster than the 25mm standpipe does when the pump is first turned off, couple of seconds vs about a minute.

[Bruce]

Bruce a weir wont fix your problem. Water will still be draining out the same size holes 

Josh

←

The holes won't be the same size...the current standpipes and 20mm and the ones in the weir are 40mm, double the size.

Bruce

[Ash]

double the size is about 4x the flow potential too just PS