Tank flow?

[Quicken]

Morning guys,

I have sketched a rough diagram of the tank (Attached in word document) I'd like to use for marine as the last one burst. I was just wondering if the flow will work as shown in the diagram as I don't want to take the risk again of drilling the tank and then also avoid the cost and effort involved.

Basically, there will be two pumps involved: one taking the water from the tank after going through the side filter overflow and the other taking the water from the sump back to the tank (They will obviously be of the same liters per hour in size).

The tank is unfortuantely only 5mm glass but the water level will sit at 450mm although the glass's total height is 600mm. The length is 1500mm and the width is also 450mm. There is a strut brace at the top keeping the glass together just above the water level, so it should keep the tank in tact (I mention this as I don't want this tank to burst as well).

Please have a look, your opinions will help me decide if i will use the tank or not.

Thanks guys.

 

[jacquesb]

Hi Quicken - what are you planning to keep in the tank? Is this question only for flow to your sump and back into your tank again?

Just remember - your return pump will loose some "pumping power" as the water heads up a "head". So, you return pump should always be bigger than anticipated...

Another thing - why don't you rather place the 1st pump (taking water to the sump) IN the sump, to rather "suck" the water from the tank, instead of pumping it TO the sump? Remember, with the sump being at the bottom, you WILL get a natural siphoning effect in ANY case.... You could actually do without the 1st pump...
I would perhaps rather suggest placing a valve (ball- or gate-valve) in the piping going doing into the sump, and in such a way you can control the amount of water being siphoned to the sump.... the same with the return piping, coming from the sump to your main display....

I can only presume that you are actually going to place some more power-heads IN the tank as well? Right?

Hope this helps.

 

[Quicken]

Yes, I have a few power heads that will go into the tank to create some waves. I think the valve idea will work well. That should ensure permanent flow if the power goes of and then come on again because there should be water in the piping. My biggest concern is the water flowing upwards from the bottom of the overflow side filter to the top of the tank and then from there down to the sump, thus the 1st pump to get the water to the top.

The other problem is the thickness of the glass, but I think that should be ok, due to the low height of the tank.

 

[viper357]

Basically, there will be two pumps involved: one taking the water from the tank after going through the side filter overflow and the other taking the water from the sump back to the tank (They will obviously be of the same liters per hour in size).

Hi Quicken, I can't really make out what exactly you want to do from your diagram, but from the quote above it appears that you want to use one pump to pump water from the tank to the sump, then another pump to take water from the sump back up to the tank ?

I would strongly advise you not to do this as it will be virtually impossible to get 2 pumps to match each other, you will end up either draining and/or overflowing one of the tanks.

The best system is to simply have one pump to take water from the sump up to the tank and let the water in the tank return to the sump via an overflow and simply let the water gravity feed into the sump.

 

[Quicken]

I have drawn a quick picture of the back of tank to show how the water will flow. There are holes at the back top of the tank which I can use to put the pipes through, but those holes are just above the water level so I cannot use them to have the water just flow through. If the holes were just a bit lower it would solve my problem.

I think that if I put a gate valve in the first outlet pipe and only one pump to get the water back into the tank from the sump it should work, but it will depend on water actually staying in the outlet pipe. If I put the gate valve in the area of pipe that goes down after exiting the tank it should keep the water there. Do you think that will work?

 

[Quicken]

Do you guys have any other advice with regards to my last post?

 

[DragonReef]

Quicken bad idea.

You will never get those pumps to balance out and as Viper has stated you will end up with one of those tanks being flooded.

There is an easier solution. Eco Aquatics (Sponsor on this forum) sells a siphon overflow box that can be fitted to almost any tank.
Drop him a line in the sponsor forum and he can give you more info on it.

 

[Hill]

The two pump idea is a really bad one. As Viper has said it will be impossible to balance them out. Rather pump up from sump to tank. Have a larger diameter pipe from the overflow to the sump. The water doing up to the sump will gravity feed back to the sump through this thicker pipe, no pump is necessary here.

 

[Tridan]

Dude the pump idea does not work as every one has said. But my concern is the 5mm glass over 1.5m even at a hieght of 450mm you are really pushing the limits. I would suggest that you do a whole lot more bracing to the top end of the tank, what thickness is the base?

 

[Kanga]

Sorry Quicken as the guys said the 2 pump idea does not work (dont worry this was the first way i thought of doing it as well)

If you have a overflow into which the water "flows" over then with fed gravity through a (hopefully 50mm pipe) to the sump and fed back via a return pump your much safer as the guys said.

The beauty of this is that if the return pump fails for whatever runs, it stops returning water, hence the water stops flowing over the weir. Just make sure the inlet pipe is not deep in the water and also has a hole above the water level to break a possible syphon

Have a look at this pic hopefully it will make some sense and you will see what we mean

Hermann

PS: 5 mm is mighty thin for this, brace, brace, brace and then brace again

 

[Tridan]

Pop goes the peroni kanga good advice there backed up by a sketch

 

[Kanga]

Pop goes the peroni kanga good advice there backed up by a sketch

No peroni sitting at the airport waiting for a delayed flight (bad weather) even the lounges are to full, found myself a nice quiet spot.

 

[millepora]

Defiantly follow DragonReef’s advice.

 

[Quicken]

Thanks guys,

This has helped a lot. I have however decided to have the tank drilled. The base is 10mm glass and was replaced after I had bought the tank with a cracked bottom. The glass is still fairly new, so drilling shouldn't be an issue. The tank has been running for the last year or so without any problems. It is braced at the top in the middle, and then the side overflow filter also braces the front and the back panel.

Would the salt water make any difference to the stability of the glass compared to fresh water (I know it doubles in weight because of the density)? I've been told that if the tank has been running for this long without issues, the salt water should make no difference to the stability of the glass.

Any advice on this one? I'm just taking shots in the dark and hopefully the glass will hold.

 

[Rory]

Sheesh Kango how do you get your tank and lights to float like that?

1.5m is rather long for 5mm glass... Fortunately the height of the water is fairly low. I would definitely go for cross braces.

 

[Quicken]

Do you mean cross braces along the length of the tank or just the width? I have drawn the top of the tank (attached) showing how it is braced now. There is quite a wide brace in the middle and the side filter is also keeping it together. Do you think it is necessary to brace it any further?

 

[Kanga]

Sheesh Kango how do you get your tank and lights to float like that?

1.5m is rather long for 5mm glass... Fortunately the height of the water is fairly low. I would definitely go for cross braces.

Hehe yes hurts my arms to hold them up like that.

Yip agreed, 5 mm is VERY thin

 

[Kanga]

Your bracing should look something like this

I would suggest you do the bottom as well


Also the fact that it it is saltwater wont make it any heavier. density will make things float easier but not make the water heavier

 

[Quicken]

What you've drawn is fairly close to how it is braced now, except for the open side of the tank, by that I mean the other side where there is no side filter. The bottom is braced, but only at the front and back, but I don't see this as a problem, as this tank has been running for a while already without a hint of problems.

I was really more concerned with the fact that the salt water would excert more pressure on the front and back panels of the tank. If the salt water does not really make a difference to the weight, it won't be an issue.

 

[Quicken]

Here's one FINAL pic of the bracing (I won't be too anal about this anymore). I just want to try and make sure the tank itself is stable for the least amount of money spent.

This should be ok right?