Advanced Reefers ATO on Closed Loop?

[coreytrv]

Can someone who understands hydraulics confirm or reject my thinking?

I'm in the process of setting up my ATO system on a hybrid reef.

It's a closed loop canister filtered DT with an secondary sump system (refugium, protein skimmer, dosing) to augment the canister filter.

Plumbing plan is here:



In a typical gravity fed sump, you have 1 body of water, in which generally, the gravity drain flow exceeds the return pump, therefore, you can set an ATO sensor in the pump return chamber of the sump, since that's where excess / water shortages will appear first.

HOWEVER, in my setup. I'm thinking there are essentially 2 bodies of water:

The closed loop DT, which has NO OVERFLOW. The canister filter sucks and returns theoretically in unison. While the secondary sump does dump into the DT, it's water level would be independent of the sump system.

The Sump system gravity drains from a tank above the DT, and pumps into it. It's gravity fed from it's own return, and from a branch of the closed loop DT.

Evaporation will occur in the DT body of water AND the Secondary Sump body of water.

Therefore I need (2) ATO's:

• 1 for the DT
• 1 for the Sump.

Does that sound right?

 

[KrisReef]

You have one system, with 3 connected bodies of water. If you add a remote chiller, and a remote skimmer you will have 5 bodies of water in the system.

Evaporation from the system will be replaced by one ato in the sump. Ato any where else is going to cause a flood.

 

[coreytrv]

In a regular gravity fed sump system, the waterline of the tank is static, the water level fluctuates in the pump chamber of the sump. ONLY when the return fails to provide sufficient water, does the DT water level drop.

In my setup however, the sump is gravity fed by it's own return, and what comes off the canister manifold.

Thus an ATO would affect the water level in the sump, but would not affect the waterline of the DT.

Don't I need to address potential evaporation at the DT separately from total water volume, which could be addressed via ATO in the sump?**

**Adding water to the sump, will not change the water level in the DT. I'll just sit in the sump, right?

 

[twentyleagues]

If I understand this correctly all evaporation should show in the dt. So the dt is where your ato sensor should reside. Where you add the ato water should not matter. Unless that water is a large volume overwhelming your gravity drain in the overhead sump, which it should not be. I have 2 125g tanks and a 300g pond set up with overhead sumps the evap shows in the dt.

 

[twentyleagues]

Forgot to add 1 ato should be the correct number. Sump should not show evap as it has no final pump chamber it is gravity drain.

 

[coreytrv]

Forgot to add 1 ato should be the correct number. Sump should not show evap as it has no final pump chamber it is gravity drain.

What do you mean by final pump chamber? 1 sump will sit below the DT and pump up to the wavemaker above the DT.

 

[twentyleagues]

What do you mean by final pump chamber? 1 sump will sit below the DT and pump up to the wavemaker above the DT.

The "lowest" point in the system. This is the end or return to the dt it is where your evaporation will show. If you have an open "sump" sending water to the dt under the tank no matter what you are calling it will be your lowest or final pump chamber. So if you have this "wave maker" sump under the tank it will show the evap for the entire system. I had 7 tanks 3 100g separate rubbermaid stock tanks as my "sump" the 100g stock tank that the water pulled from to go back to the system was where the evap happened or showed, the final chamber, or return chamber whatever you want to call it.

 

[coreytrv]

Ok, thank you...that explanation helps, but I'm still not quite there.

Lowest point in the system shows evaporation, that makes sense, because water will accumulate there, and more/less water will show itself via the level in the final pump chamber. This is because in normal overflows, the waterline is set at the DT by the overflow box, and everything accumulated in the below grade sump.

However, in my system, there is no gravity drain FROM the DT. There is an overflow box, but it's driven by closed loop suction. Meaning excess water in the DT, will not automatically drain to the low point, rather it will sit in the DT, unless removed via a pump.

Conversely, a water shortage will not automatically be replaced by gravity inflow FROM the wavemaker either, since that will only change if the sump runs dry, and doesn't provide enough flow. It has no mechanism to replace water that evaporates from the DT.

The only gravity drains in this system are from the equalizing tank (wave maker) into the DT, and the remote sumps.

If too much evaporation takes place in the sump system, pump runs dry nd flow doesn't return to the DT...but that problem is separate from changes in water level at the DT from evaporation....I think

 

[twentyleagues]

This is pretty complicated. What supplies water to the wave maker sump? There is a pump from this wave maker to the dt though yes? this is basically to confirm my thinking. If there is constant supply and removal of water in this wave maker sump it should stay level.
I really think after all is said and done all your evap will occur in the dt. So ato sensor in dt ato line to dt should be good.

 

[coreytrv]

This is pretty complicated. What supplies water to the wave maker sump? There is a pump from this wave maker to the dt though yes? this is basically to confirm my thinking. If there is constant supply and removal of water in this wave maker sump it should stay level.
I really think after all is said and done all your evap will occur in the dt. So ato sensor in dt ato line to dt should be good.

The wave maker will be supplied by (2) lines shown by red arrows:

1. A branch from the closed loop canister filter manifold
2. Return pump from the remote sump.

The wave maker is a surge filter that uses a bell siphon design credit to @TangerineSpeedo, his post below:

Large Build - Remote Sump Question (NO GRAVITY)

Looking for guidance on plumbing a remote sump into a 500 gallon reef tank that will be filtered via the fish room in the garage, some 30'+ away. All single story, gravity feed not an option. Filtration is a bead filter, closed loop. Initially I had planned a sump in the attic, above the DT...

www.reef2reef.com

The surge chamber will fill with a combination of water from (1) the filter manifold, and (2) the remote sump.

That said, while I think evaporation will show in the refugium sump, it will also show in the DT, if not addressed with replacement RODI water.

 

[KrisReef]

I don’t know how this system works.
-surge systems by nature are difficult (impossible?) to operate on with an ATO sensor trying to keep up with the surge movement and water level changes.

If all the boxes are connected the evaporation can be replaced at one point anywhere that the system shows a drop in water level as a consequence of evaporation. It can even work in a DT with surge, in theory.

 

[twentyleagues]

I still think it will be dt that will show evap not the refugium. But like @KrisReef said with a surge happening you might have issues with the sensor. Hopefully I am incorrect and you can get your sensor level from the fuge. I dont think so though.

Edit just got home from work I think I was thinking the one labeled refugium was only gravity drain. I see now there is a pump that pumps water out of the refugium, the pic with red arrows didnt load at work. So that is most likely where your evap will show and where the sensor for the ato should go. As for where the ato water should go I would add it there also that should be the best way to manage evap. There is a lot going on and this is a pretty complicated system on paper maybe in real life it wont be so confusing.