Trying to assemble 3 aquariums together

[Aqua Splendor]

I'm concern about the Input flow to the display tank, (Purple circle part) I'm not sure what would happen, is it going to make sound? Can air circulate if the opposite is full submerge in water??
 

Does the alternative could work correctly if the pipe goes far beyond the bottom of the display tank and come back in a U shape to the output?

Do you see any risk that I should be concern, clog, atmosphere pressure, air stock, possible overflow, etc... 
thank you

I'm trying to make my live easier by combining aquariums together sharing the same water.

[seabass]

Hmm...  I can't say for sure what to expect.  I don't see where there could be anything like a siphon break to stop flow.  Although, I expect that the water level in the plumbing (circled in purple) will want to stay at the water level in your display.  So the water overflowing from the frag tank will likely fall to the level of the display.  This might make some noise and create air bubbles.  I anticipate either option to be roughly the same.  Your solution does help deal with excessive back flow from two tanks into one sump (by limiting it to one tank).

 

I would guess that the closer the overflow of the frag tank is to the water level of the display, the less of a waterfall that will exist inside the plumbing.  This might help to limit the noise and air bubbles. 

 

Another option might be to setup the display more traditionally (with a typical return supply and overflow).  Its overflow could supply the frag tank (as it would a traditional sump), but the frag tank would have an overflow instead of a return pump.  The frag tank's overflow would go to the third tank (the sump), which would house the return pump (supplying the display).  This would put the display up top.  The frag tank might get bubbles from the overflow supplying its water.

 

Yet another option would be to have both your frag tank and display have their own overflows into a (shared) sump.  The sump would have to be able to handle the back flow of both tanks in the event of a power outage.  You could either have two return pumps, or share one.  Not a bad option IMO.

 

Finally, and maybe my favorite option (depending on if you don't currently own these tanks), is to setup a traditional display, and a sump which houses a coral frag section (versus the more typical macroalgae refugium).  This would allow you to do the same thing with only two tanks, and would provide for a more traditional plumbing setup.

[Aqua Splendor]

Yeah, I think the height return flow from frag to display is probably wrong and should be at the same level as the overflow box at least. I guess a bigger bulkhead would help the drain too. I do fear those bubble too like you said hmm..

I made an order for a second overflow box (I have the fiji cube 400gph) for the frag tank, I could try your option, instead of just a bulkhead on the frag tank

 

Quote

Another option might be to setup the display more traditionally (with a typical return supply and overflow).  Its overflow could supply the frag tank (as it would a traditional sump), but the frag tank would have an overflow instead of a return pump.  The frag tank's overflow would go to the third tank (the sump), which would house the return pump (supplying the display).  This would put the display up top.  The frag tank might get bubbles from the overflow supplying its water.

Not sure to understand your option about display filling the frag tank, the frag tank is higher than the display, height level speaking.
 

I decided yo go with a more traditional route by buying a second overflow box, but I guess I can try different setup and if it failed I will simply go with traditional and the sump would basically be what tanks shared together. Though I'm concern about the volume of water it can hold with the two tank from power outage.

 

Left, my AIO frag tank, on right the display tank, being like this for 3-4 years. 

Hard to see but in the left bottom corner where is the electric stuff chaos, I was thinking to use that aquarium as a sump, going under the display tank on the right.


And this is the actual tank display, which is my lab tank, AIO. This is the one I would transfert to the other tank (same size, just without acrylic separation for AIO) 

[seabass]

26 minutes ago, Aqua Splendor said:

I'm concern about the volume of water it can hold with the two tank from power outage.

You'll want the return outlet to be as high as possible to reduce the amount of back siphon.  Also, obviously, the more water the sump can handle, the better; so keeping the water level low in the sump will allow it to hold more water during an outage.  Is a bigger sump an option?

[Aqua Splendor]

I have another aquarium that could be used as a sump, currently a vivarium ishh that could fit on the side, it's my option #2.
 

Sump #1:

Length: 50cm

Width: 25cm
Height: 30cm

Total volume: 37 Liter

Sump #2

Length: 60cm

Width: 30cm
Height: 36cm

Total volume: 64 Liter

Frag tank

Length: 90cm

Width: 40cm
Height: 30cm

Total volume: 108 Liter

 

Display Tank

Length: 60cm

Width: 45cm
Height: 45cm

Total volume: 121 Liter

[mitten_reef]

On 5/7/2022 at 6:25 PM, Aqua Splendor said:

I'm concern about the Input flow to the display tank, (Purple circle part) I'm not sure what would happen, is it going to make sound? Can air circulate if the opposite is full submerge in water??
 

Does the alternative could work correctly if the pipe goes far beyond the bottom of the display tank and come back in a U shape to the output?

Do you see any risk that I should be concern, clog, atmosphere pressure, air stock, possible overflow, etc... 
thank you

I'm trying to make my live easier by combining aquariums together sharing the same water.

why make it into the "waterfall"?  why not just make two separate supply-return loops from the sump, you'll eventually share the same water parameters just the same.  the noise wouldnt have been my biggest concern linking the frag and the display together, keeping the water moving at the correct rate would be.  

 

 

[Aqua Splendor]

Short answer: I don't have money

 

But I end up buying a second overflow box for the Frag. Wanted to spend 50$, end up spending 500$ for just the plumbing arrgg.

 

And yes the flow rate was a concern too. I thought about using bigger bulkhead from frag to display to prevent a potential problem.

 

I might give some try on doing hybrid solution.

Something a bit weirdo I thought:

 

Was thinking to use a T pipe connection for the overflow box, both drain connected ending up as one pipe in the sump. It defeat the purpose of emergency drain a little bit in a way but when I connect the Frag tank that would give me 4 vinyl pipe in the sump and I don't like this... idk I want to test this 😅

[mitten_reef]

10 hours ago, Aqua Splendor said:

Was thinking to use a T pipe connection for the overflow box, both drain connected ending up as one pipe in the sump. It defeat the purpose of emergency drain a little bit in a way but when I connect the Frag tank that would give me 4 vinyl pipe in the sump and I don't like this... idk I want to test this 😅

iteration of this would be standard overflow box on each tank (one drain, one e-drain), each piped into the T, making only one drain pipe + one emergency pipe entering sump.  One of the drain, or both will need some sort of valve to dial in the flow rates

Then, put a T, or a Y splitter, on the return side as well. not sure if you need valve(s) on the return