Peninsula closed loop design

[Fiziksgeek]

I put down a deposit with CDA for a large peninsula before the new year, current production times about 3-4 months, so I wanted to get my place in line even though I hadn't finalized the design fully. The tank overall will be 72x36x26 peninsula, 24" modular marine overflow (3x1.5" bulkheads) and 1" returns on each side of the overflow. I am planning to put 2-4 MP40s, maybe mp60s on the overflow end, but like most folks, don't want any power heads on the 3 viewable sides. In order to really get more flow at the far (viewable) end of the tank, I really think a closed loop is the way to go.

My thought is to have 4 x 1" outlets, concentrated at end of the tank.

From there I had two thoughts on the intake and pump.

A. Single Abyzz A200 with a 2" intake drilled in the bottom of the tank, maybe 1' from the overflow end, centered in the 36" width. I am going to use an Abyzz A200 as my return pump from a remote sump in the basement. Not that I like the idea of keeping a $2000 pump on the shelf, but I could in theory have a single spare that could replace either should the need arise.

B. Two Vectra L2s, each with their own intake on the overflow end panel, each would feed two returns. A little more total flow than a single A200, much cheaper. Concerned about leaving enough room for vortecs' between the sump returns and 24" overflow, its already a busy panel. I suppose it would be possible to put the 2x1.5" intake on the bottom panel like option A.

Thoughts, 1 pump or 2, intake(s) on bottom or end of the tank?

 

[Dakota_reef]

I'm going to be drilling a closed loop for my 150, and as of today, I'm leaning toward 2 pumps, 1 input each and 1 output each. 1 1/2" inputs through the back and 1" outputs at the surface level (two 3/4" eductors on locline each side).

I'm trying to avoid expensive powerheads and the cost of two external pumps is still way cheaper than 4 Vortecs. I'll probably go one Reeflo Dart and one external DC pump for random flow (Vectra is on my short list).

My return pump is gong to be ~ 600 gph pushing water toward the front of the tank to swirl it all around.

 

[Fiziksgeek]

I'm going to be drilling a closed loop for my 150, and as of today, I'm leaning toward 2 pumps, 1 input each and 1 output each. 1 1/2" inputs through the back and 1" outputs at the surface level (two 3/4" eductors on locline each side).

I'm trying to avoid expensive powerheads and the cost of two external pumps is still way cheaper than 4 Vortecs. I'll probably go one Reeflo Dart and one external DC pump for random flow (Vectra is on my short list).

My return pump is gong to be ~ 600 gph pushing water toward the front of the tank to swirl it all around.

Whatever I decide, my plan would be to match the inlet size to the pump, for the Abyzz that would be 2", for a Vectra L2 it would be 1.5". Here is what I was thinking as my options.

 

[Vivid Creative Aquatics]

Love closed loops and very interested in the direction you are taking this tank.

I like the idea of the drains for the loop on the back wall, as opposed the floor of the tank - if you decide to go with sand, it wont interfere, plus the drains on the back wall will help to some extent with drawing water back in that direction.

I think your plan will work well, but it might be better to spread out the loops just a bit more. Maybe move the two left inlets a little close to the center of the tank

Another option - and this might be the best in terms of getting movement throughout the tank, is to stagger the placement of the inlets. If you point them in the right directions , this might create some really interesting flow

Then - add our Random Flow Generator Nozzles to these loops for a broad randomized flow. This would fill this tank will movement.

 

[Fiziksgeek]

Love closed loops and very interested in the direction you are taking this tank.

I like the idea of the drains for the loop on the back wall, as opposed the floor of the tank - if you decide to go with sand, it wont interfere, plus the drains on the back wall will help to some extent with drawing water back in that direction.

I think your plan will work well, but it might be better to spread out the loops just a bit more. Maybe move the two left inlets a little close to the center of the tank

Another option - and this might be the best in terms of getting movement throughout the tank, is to stagger the placement of the inlets. If you point them in the right directions , this might create some really interesting flow

Then - add our Random Flow Generator Nozzles to these loops for a broad randomized flow. This would fill this tank will movement.

Thanks for the reply, this thread has stagnated a bit, and I have not made any final decisions. I do like your idea, but if I recall there was build thread where a similar layout was used and after setting it up, the owner wished he hadn't staggered them. I'll have to see fi I can find that and see what the reasoning was.

 

[Vivid Creative Aquatics]

Thanks for the reply, this thread has stagnated a bit, and I have not made any final decisions. I do like your idea, but if I recall there was build thread where a similar layout was used and after setting it up, the owner wished he hadn't staggered them. I'll have to see fi I can find that and see what the reasoning was.

I'd be interested in seeing that thread as well. I could see the staggered idea not very well with standard jet or round nozzles, as it would create very narrow flow patterns that may not interact much with each other.

 

[reef_ranch]

I built a closed loop on my 340 AGE peninsula with pvc bottom that works well. I’m running 2 RD3 240w pumps fed by two 2” inlets set about 8” up the back wall. The inlets are joined by a 2” tee then split into 2 1.5” pipes to feed the pumps. Each pump feeds 3 1” outlets spread across the bottom in two rows on either side of the rock structure. Each outlet has a ball valve to balance the flow and a random flow generator. The pumps are controlled by my Apex, ramping them them up and down to create strong chaotic flow up and over the rock structure. Definitely great way to generate good flow for the tank although I do supplement because you can never have too much flow!

 

[csund]

Here you go!

Panta Rhei is Reinventing the Closed Loop with an all NEW Pump Design | Reef Builders | The Reef and Saltwater Aquarium Blog

Closed Loops are a forgotten art form of water movement in the reef aquarium space, providing incredible flow rates throughout the aquarium while removing the equipment from the primary display tank.

reefbuilders.com

My panta rhei power heads have been flawless

 

[Fiziksgeek]

Here you go!

Panta Rhei is Reinventing the Closed Loop with an all NEW Pump Design | Reef Builders | The Reef and Saltwater Aquarium Blog

Closed Loops are a forgotten art form of water movement in the reef aquarium space, providing incredible flow rates throughout the aquarium while removing the equipment from the primary display tank.

reefbuilders.com

My panta rhei power heads have been flawless

There is so little information out there about the Hyrdo tubes. At this point, I wouldn't even consider them.

 

[Fiziksgeek]

I built a closed loop on my 340 AGE peninsula with pvc bottom that works well. I’m running 2 RD3 240w pumps fed by two 2” inlets set about 8” up the back wall. The inlets are joined by a 2” tee then split into 2 1.5” pipes to feed the pumps. Each pump feeds 3 1” outlets spread across the bottom in two rows on either side of the rock structure. Each outlet has a ball valve to balance the flow and a random flow generator. The pumps are controlled by my Apex, ramping them them up and down to create strong chaotic flow up and over the rock structure. Definitely great way to generate good flow for the tank although I do supplement because you can never have too much flow!

So that would be more similar to my option B above, inlets on the overflow end with outlets spaced across the bottom.

I am a little confused by your plumbing though. You say there are qty 2-2" inlets. You then join those inlets with a tee, then split them again, but into 1.5" pipes to feed each pump? I thought the inlets to the large red dragons were 2", so you would want to match that size so as not to restrict the inlets. I assume joining them together is for some redundancy if one of the inlets were to clog?

 

[reef_ranch]

So that would be more similar to my option B above, inlets on the overflow end with outlets spaced across the bottom.

I am a little confused by your plumbing though. You say there are qty 2-2" inlets. You then join those inlets with a tee, then split them again, but into 1.5" pipes to feed each pump? I thought the inlets to the large red dragons were 2", so you would want to match that size so as not to restrict the inlets. I assume joining them together is for some redundancy if one of the inlets were to clog?

The original reason for joining the two inlets was to feed three pumps and for redundancy in case an inlet became covered I removed one pump after seeing that I was running each pump at max 50% without roiling the water so much it would splash up and over the eurobrace. With two I can ramp them up to full power and still keep water in the tank.
Yes, I do step them down to 1.5" to feed the RD3s. The equal sizing between inlet and outlet works fine because the pumps are 2' below the tank and thus pressure fed. I also use a 240W RD3 as my return pump which I do not step down as it has to draw the water from a low static sump level.

 

[csund]

There you go!

https://jtl-shop.panta-rhei-aquatics.com/Hydro-Tube-42-Set_1

It looks like it sucks water from the inlet and pushes water out the outlet at 3000 gph!

If it’s built anything like the power heads it would be top notch.

That being said I run an Abyzz pump for my return and also one to power my Venturi skimmer and they are great too. Both have been running for a year and half and still have yet to clean them.

Both move water but the Hydro tube would probably be a lot cleaner installation. The one benefit to Abyzz would be built in 0-10v but you still need the 200$ adapter. The Panta Rhei controllers connect via canbus but they offer a “analog in” instead of their typical USB controller. With that you can use 0-10v. I think it controls more than one pump as well. My USB controller controls all my Panta Rhei pumps.

 

[Dakota_reef]

Now you all have me questioning if I should drill from the bottom. So far, I've decided to use two 1 1/2" intake's that feed a Reeflow SuperDart's 2" opening and then have a 1 1/2" return "spray bar" with two RFGs on it. I kind of plan on a negative space design to hiding things from the bottom might prove difficult.

 

[Fiziksgeek]

There you go!

https://jtl-shop.panta-rhei-aquatics.com/Hydro-Tube-42-Set_1

It looks like it sucks water from the inlet and pushes water out the outlet at 3000 gph!

If it’s built anything like the power heads it would be top notch.

That being said I run an Abyzz pump for my return and also one to power my Venturi skimmer and they are great too. Both have been running for a year and half and still have yet to clean them.

Both move water but the Hydro tube would probably be a lot cleaner installation. The one benefit to Abyzz would be built in 0-10v but you still need the 200$ adapter. The Panta Rhei controllers connect via canbus but they offer a “analog in” instead of their typical USB controller. With that you can use 0-10v. I think it controls more than one pump as well. My USB controller controls all my Panta Rhei pumps.

I'll stand by my statement that there is so little information about the Hydro tube that I wouldn't considering using it. I am all for trying new things, but I am not going first! haha Show me a couple builds where they have been used and how they were implemented and I'll consider them...Specifically, how are they plumbed? we typically think about an inlet and one or more outlets. The inlet needs to be sized not to restrict flow, and the outlets are chosen to put the flow where we want it. If water will flow both ways, how do you plumb this? would love to see some examples...would love to see any examples....

 

[Fiziksgeek]

Now you all have me questioning if I should drill from the bottom. So far, I've decided to use two 1 1/2" intake's that feed a Reeflow SuperDart's 2" opening and then have a 1 1/2" return "spray bar" with two RFGs on it. I kind of plan on a negative space design to hiding things from the bottom might prove difficult.

I think about closed loops in 3 ways:

1- Risk - Obviously, if there is a leak in the lowest bulkhead, the tank could potentially drain to this level. Drilling the bottom of the tank means the entire tank empties and everything dies. IMO, a catastrophic fast leak is unlikely. What is possible, is a small/slow leak, which would be incredibly painful to deal with because you would have to empty the tank to fix it, but the risk of the tank emptying onto the floor quickly is unlikely. I plan to use Schedule 80 bulkheads to make the most robust connection possible.

2 - Looks - Based on my desired aquascape and potential plumbing design, will I be comfortable with the look of the closed loop. This is highly subjective and some people will work harder to hide the plumbing than others. Some are OK seeing a bit, some want to hide everything and make it invisible to the viewer. I ask will I be happier looking at powerheads or with partially hidden plumbing. Can I make the aquascape I want work with the plumbing I am planning?

3 - Efficiency - Am I willing to pay more to run the tank for the look? Propeller style power heads will more more water with less electricity. Am I willing to pay more for "hidden" flow?

For me, I think the risk is manageable, I am willing to give up some efficiency, and because I an doing a peninsula tank and do not want to see power heads, to get good flow throughout the tank, a closed loop is almost a necessity.

 

[Dakota_reef]

I think about closed loops in 3 ways:

1- Risk - Obviously, if there is a leak in the lowest bulkhead, the tank could potentially drain to this level. Drilling the bottom of the tank means the entire tank empties and everything dies. IMO, a catastrophic fast leak is unlikely. What is possible, is a small/slow leak, which would be incredibly painful to deal with because you would have to empty the tank to fix it, but the risk of the tank emptying onto the floor quickly is unlikely. I plan to use Schedule 80 bulkheads to make the most robust connection possible.

2 - Looks - Based on my desired aquascape and potential plumbing design, will I be comfortable with the look of the closed loop. This is highly subjective and some people will work harder to hide the plumbing than others. Some are OK seeing a bit, some want to hide everything and make it invisible to the viewer. I ask will I be happier looking at powerheads or with partially hidden plumbing. Can I make the aquascape I want work with the plumbing I am planning?

3 - Efficiency - Am I willing to pay more to run the tank for the look? Propeller style power heads will more more water with less electricity. Am I willing to pay more for "hidden" flow?

For me, I think the risk is manageable, I am willing to give up some efficiency, and because I an doing a peninsula tank and do not want to see power heads, to get good flow throughout the tank, a closed loop is almost a necessity.

Those are really good considerations.

I think #1 is why I don't want to put them through the bottom. a leak on the back wall can be remedied "easier" than through the bottom, but I don't know how often a bulkhead fails while in use. I"ve not had any of mine fail, and one tank was a Planted tank at pH 6.5-6.8 and the rubber seals were find years later when I broke it down.

#2 is why I'm doing a closed loop. slapping powerheads everywhere used to be something no one wanted to do (I originally converted powerheads to CL in my 50g tall to clean it up). I also want to look down the length of my tank, so powerheads will prevent that if they are on the side.

I have solar, so #3 isn't cost related, but HEAT might add up with high wattage centrifugal pumps. Can't afford them fancy Abyzz yet.

 

[Gundy]

I am considering a closed loop as well but I am worried about a failure within the loop. What would be an emergency plan or fail safe plan if you get a leak on a fitting or a leak somewhere in the system?How would you going to keep the tank from completely draining? I assume a check valve would be installed but all it takes is a small piece of sand to allow the valve to fail.

 

[Dakota_reef]

I am considering a closed loop as well but I am worried about a failure within the loop. What would be an emergency plan or fail safe plan if you get a leak on a fitting or a leak somewhere in the system?How would you going to keep the tank from completely draining? I assume a check valve would be installed but all it takes is a small piece of sand to allow the valve to fail.

That's a risk, but if you seal the bulkhead correctly you shouldn't have a problem. My other tank's bulkheads have never leaked, plus anyone with an overflow box has bulkheads on the bottom already.

I plan to have my bulkheads high enough that if I have to, I can drain the tank to access it for repair/replacement. Mine will also have threaded fittings so it's easier.

 

[reef_ranch]

I have had the valves under the bulkheads spring slow leaks in the past. No problem taking them out without draining the tank. The bulkhead is threaded inside the tank. I simply thread in a cap, close the other valves and drain the water in the pipe. I can then remove and service the valve. I'm not at all worried about the bulkheads themselves leaking. They are schedule 80 with thick gaskets and when I installed them I applied a thick ring of silicone around each bulkhead. I installed the tank in 2014 and other than replacing o-rings in most of the valves, I've not had to service the plumbing at all. The pumps are serviced a couple of times a year.

If you are still concerned, take a look at Vivid Aquarium's 800g display. The closed loop exits (I thing there are 12) are fitted into the eurobrace. I think they use 6 or 8 Vectra pumps to generate the flow. It creates a ton of flow which can easily be directed anywhere in the tank. I'm not sure where the pump intakes are, either they pull from the overflow or there are bulkheads on the back wall.

 

[Gundy]

What about placing 2 -4 large volume Tunze power heads in the tank and placing them inside the rocks in strategic locations on the far side of the tank. They even have a rock with the plastic ring to mount it in or make your own. Seems like a lot more “safe“ option without all the plumbing hassles and possible leaks in a closed system.