2nd tank lower than sum plumbed to the main?

[karimwassef]

I want to add a second tank to my conventional DT and sump setup.

The catch is that it's not at the DT's level or at the sump's level. It about a foot below the sump.

Another complication is that I don't want to turn it into the sump of this combined system. My ATO works great as it is at the last stage of the current sump.

So... My current thoughts revolve around using an overflow in my sump's first stage (to prevent the sump from emptying to the lowest tank) and then likewise an overflow in the lowest tank that connects to a pump that delivers water back into the sump.

 

[ReefingWerewolf]

Why not have the water from your DT overflow box go strait down to your new tank then pump it back up to the sump then pump it from your sump back to your DT.

Good luck.

 

[karimwassef]

How do I control the level is the second tank?

I guess I can use an overflow in the second tank and connect that to the pump...

Also, I would have to use a special overflow from the DT since this smaller second tank couldn't handle it when the power goes out. I'm think maybe a smaller overflow with a valve to reduce the flow to the second tank compared to the normal flow to the sump?

 

[ReefingWerewolf]

I like this, now you have got me thinking...

 

[ReefingWerewolf]

Why not convert your emergency overflow (assuming you have one) into a secondary return line. It would function like a second sump in that it has a pipe from your overflow box bringing water down to it and a return pump.

 

[ReefingWerewolf]

As long as your new tank was big enough flooding shouldn't be an issue.

 

[ReefingWerewolf]

WAIT, I just got another idea!!!!!

 

[ReefingWerewolf]

Get two ato dosing pumps such as the sprectrapure or brs and attach them above both tanks. Then have them running at EXACTLY the same amount a minute. Next setup two float switches in your new tank. So you would have a small amount of water being transferred between the two tanks at all times. And to make sure you dont flood your new tank or your DT you would setup two float switches ( one just above and one just below your desired new tank water level) in your new tank so if one pump was taking more than the other and the water level was changing it would trigger one of your float switches automatically turning off both pumps. One other safety you could easily setup if you have an apex of a reefkeeper controller is that if one of the pumps stops working the apex/reefkeeper would cut the power to the remaining running pump so you dont flood.

Just some brainstorming of mine, Good luck

 

[dattong]

I want to add a second tank to my conventional DT and sump setup.

The catch is that it's not at the DT's level or at the sump's level. It about a foot below the sump.

Another complication is that I don't want to turn it into the sump of this combined system. My ATO works great as it is at the last stage of the current sump.

So... My current thoughts revolve around using an overflow in my sump's first stage (to prevent the sump from emptying to the lowest tank) and then likewise an overflow in the lowest tank that connects to a pump that delivers water back into the sump.

It should work, but you need to make sure to have the overflow box installed low enough in your second DT so it can take all the extra water form the sump and the main DT when power is off.

 

[ReefingWerewolf]

Whoops

 

[Bergenholtz]

If 2nd tank is lower than sump how can overflow work?
Overflow box works with gravity. If its lower, it won't work.

I am guessing the only way to work this is to add a pump that is equivalent to the water flow coming in to the 2nd tank and just pump it back up. Otherwise, you have to switch sump and 2nd tank.

 

[dattong]

Don't make it too complicated guys. Just use the second DT as if it was a sump with only two sections, a huge fuge and a return (which is an ovwerflow box). However, you need to make the overflow box big enough to house a pump in there to pump water back into the sump. So in this set up, you need to run 2return pumps , one going from second DT to the sump and the other going from the sump to the first DT. It's just like running two independent tanks that share the same sump. I would not use dosing pump method because it will fail eventually.

 

[ca1ore]

Trouble is, the lowest vessel always ends up being the 'sump' where evaporation will 'magnify' and levels drop. The only way I can think of to manage this would be to divert some overflow from the system to the lowest tank and have a float switch controlled pump pushing water back up to the main sump. Matching pump flow to incoming overflow will be tricky, and won't stay, so you would want the pump to be pushing water faster than incoming so the float switches (use at least two, redundant) will allow the pump cycle and maintain levels within an inch or two. Is a significant potential failure point if the pump should fail, so you'd want to make sure the new tank could hold all system overflow water just in case. Frankly, I'd not do it, just too complicated.

 

[karimwassef]

This needs to be a simple and passive system that can handle a power loss and use only one ATO and float into the original sump.

The DT is 380 gal. The sump is 180 gal.
The small tank is 100 gal.

Dattong is where I'm at... Low complexity, simple, self adjusting system.

If I take some overflow in the DT and run it to the second tank, then have the overflow in the second tank run a return line to the sump, then the second tank is essentially a second sump... The only restriction is that the flow rate to it is highly constricted (valve) so it doesn't endure the power-off overflow - the real sump will absorb it first.

The only question remaining is... Will the original sump ATO be sufficient for the system to work?

 

[ca1ore]

If I take some overflow in the DT and run it to the second tank, then have the overflow in the second tank run a return line to the sump, then the second tank is essentially a second sump... The only restriction is that the flow rate to it is highly constricted (valve) so it doesn't endure the power-off overflow - the real sump will absorb it first.

Won't work! You need some way of automatically adjusting the levels in the new tank to account for variations in the overflow and the return. If you do it as you propose, sans float switches, you WILL either have an overflowing tank or it will run dry.

 

[karimwassef]

The second tank overflow maintains its water level. The hope is that because it is a slow loop 'sump', the main sump's ATO will be sufficient to maintain the system's water level.

 

[Gatorfan]

The problem is, an overflow won't work if the water has to go 'up' from the tank it's on.

 

[dattong]

My setup is similar to this.

More info:

The second display will take all the extra overflow water when power is off.

 

[thegrun]

You must use the overflow box in the low tank as the return pump section. This return pump section must be large enough to hold all the drain down water from the high DT and the sump when power is lost of you will have a flood. The sump must drain into lower DT. The upper DT could drain either into the sump or the lower DT, but if it only drains into the lower DT you would need to pump some of the lower DT water bck up into the sump.

 

[thegrun]

My setup is similar to this.

More info:

The second display will take all the extra overflow water when power is off.

Perfect!