To closed loop or not?

[Brew12]

Awesome. I love this stuff. Thank you for all the great info. Maybe this winter I will switch back to my Iwaki.

Iwaki makes a great pressure rated pump, but they are not very efficient. That is one of the trade offs you get with the pressure rated pumps. You do get bigger efficiency gains by using a DC pump on a basement sump (although some DC pumps fall well short of their advertised max pump head!). The fact the DC pump can ramp up to speed slowly allows the use of a more efficient impeller design. The same impeller on an AC pump could keep it from starting reliably.

I just think it would be easier to circulate water from the tank and through the sump. How do you circulate water between your display tank and your sump, if you are using a closed loop? If this can be done easily enough, maybe I'll add a sump.

It is typically done with 2 separate systems. You just set up a sump with constant flow just like you would if you had power heads. Then, instead of power heads, you create a variably flow closed loop system. They operate completely independent of each other.

"I don't apologize for my ignorance. I just owe an apology if I'm not willing to learn."

Grey Guy

That is a fantastic quote!

 

[Grey Guy]

Iwaki makes a great pressure rated pump, but they are not very efficient. That is one of the trade offs you get with the pressure rated pumps. You do get bigger efficiency gains by using a DC pump on a basement sump (although some DC pumps fall well short of their advertised max pump head!). The fact the DC pump can ramp up to speed slowly allows the use of a more efficient impeller design. The same impeller on an AC pump could keep it from starting reliably.

It is typically done with 2 separate systems. You just set up a sump with constant flow just like you would if you had power heads. Then, instead of power heads, you create a variably flow closed loop system. They operate completely independent of each other.

So, are you saying that your sump and display tank are not connected at all. If the "sump"

Iwaki makes a great pressure rated pump, but they are not very efficient. That is one of the trade offs you get with the pressure rated pumps. You do get bigger efficiency gains by using a DC pump on a basement sump (although some DC pumps fall well short of their advertised max pump head!). The fact the DC pump can ramp up to speed slowly allows the use of a more efficient impeller design. The same impeller on an AC pump could keep it from starting reliably.

It is typically done with 2 separate systems. You just set up a sump with constant flow just like you would if you had power heads. Then, instead of power heads, you create a variably flow closed loop system. They operate completely independent of each other.

Are you saying that your sump is isolated from your display tank?

 

[mcarroll]

Back Then
Closed loops are from the 1990's.....before the Age of Powerheads.

They were a great innovation in their time – the closed loop removed the extra plumbing between the tank and sump and more or less took the limits off of plumbing size. Those were the two main weaknesses of flowing your reef from the return pump.

Powerheads of the day were built for running undergravel filters or garden water fountains, so there really was no competition.

Today
Powerheads of today are definitely better in every way that flow can be better. They are cheaper, more flexible, better and more variety of flow characters available, less power needed, no significant presence outside the tank (except for one brand), the list goes on.

You could make any closed loop system better by doing nothing more than shutting down the CL pump and covering every outlet on its manifold with a powerhead.

Even WetWebMedia drew this conclusion (in 2015): http://www.wetwebmedia.com/pbretfaq3.htm

From the link "For me; they're an inferior idea, technology."

That's a concluding statement, so out of context – it was not put bluntly like that....read the link!

So u can put a tunze under a rock cool how do u hide the power cord? Under the sand then when u go to clean the tunze equals a mess.

My guess is that you'd never be forced to clean them when installed like this.

But this is your hypothetical example – how's algae going to grow on a covered pump?

Mine already go 1-2+ years between cleanings sometimes (don't tell @rvitko ), and that's out in the light growing algae.

@Grey Guy the return would be a separate "loop". You'd have a drain to the sump, and a pump down there to bring the sump-filtered water back up to the display tank.

 

[Grey Guy]

I bought 600 dollars worth of power head, and they all quit working. With a closed loop, I only need 1 pump, and a standby replacement. Power heads can be great additions to a tank too. It's just a matter of choices, not what's right or wrong.

 

[IvanW]

I am using a closed loop and love it,I run it off of a Red Dragon 230 connected through an Apex. It gives great adjustable flow and I can't see those ugly pumps in my tank. I have one large powerhead in the tank that is hidden behind a rock structure,the only reason I put it in is I had it lying around and figured the extra flow would not hurt.

 

[mcarroll]

I bought 600 dollars worth of power head, and they all quit working. With a closed loop, I only need 1 pump, and a standby replacement. Power heads can be great additions to a tank too. It's just a matter of choices, not what's right or wrong.

True. And I was being a little over the top to make a point....that's old tech.

If you have a tank running on a closed loop, I wouldn't go busting up a good thing just to install some power heads.

But if that one big pump stopped working, I'd probably give serious consideration to a switch.

 

[Brew12]

True. And I was being a little over the top to make a point....that's old tech.

Bellbottoms made a come back in the 2000's...

I actually see a future where closed loop systems make a comeback. If gyre flows become the next big trend (as it seems they may be) then closed loop systems could become the easiest way to produce that flow pattern. Especially in larger tanks.

 

[mcarroll]

Bellbottoms made a come back in the 2000's...

I actually see a future where closed loop systems make a comeback. If gyre flows become the next big trend (as it seems they may be) then closed loop systems could become the easiest way to produce that flow pattern. Especially in larger tanks.

LOL

LOL

Bellbottoms. I know. (Child of the '70's so you won't catch me going there again.)

I still use regular, AC-powered Nanostreams to do that kind of flow. I hesitate to say "it's nothing special" since it's my favorite way to flow a tank.....but it doesn't take a very special pump or setup to do it. It might be harder to pull off with a wider-flow pump, but I think about any flow pump should be capable.

Off-hand the only closed loop system I'd like to see is one that was built to be all-internal to the display tank – pump and all – and so that it could be broken down and reconfigured as needed. If it didn't need any weird holes in the tank and there was no permanent installation, it could be fun to mess with one.

 

[Upstartreefer]

Hey everybody. I did know this tread was active again. We have been busy building our new home. Just to let everyone know that has been following along I have ordered my new aquarium from Miracles In Glass. It's 260 gallon 84X30X24 and I am super excited about getting it set up and starting a build tread.

@Brew12 after our discussion I decided to go with the closed loop system for 2 reasons.

1) I wanted the least amount of clutter in my main display.
2) With your idea of making a front to back gyre with one of my L1 pumps and side to side gyre the other L1.

With each of the pump 3 outlets and able to run the same modes as the MP models I think the flow veritable and strong enough.

Thoughts?

 

[Brew12]

2) With your idea of making a front to back gyre with one of my L1 pumps and side to side gyre the other L1.

I wish I could remember what I was thinking... couldn't find it in the thread. Going front to back would be very interesting. I am still considering this as an option as I plan a new system but if I do go this route, I will go with suctions and returns on each end so they flow opposite each other.

Now you are making me want to play around with this. I might have to rig up a closed loop that I can hang over the sides of my existing system to see how the flow patters look.

 

[Upstartreefer]

@Brew12 post #92. Yes, you would have no problems going with 2 suctions. I think that would actually be wise. If I decide to go with a closed loop I would do it much differently than I have ever actually seen. I wouldn't discharge through nozzles at all. I would create a discharge header using furniture grade PVC with holes drilled in it across the length. I would do at least 3 suctions on the other end of the tank. It would work like a gyre on steroids.

 

[Brew12]

@Brew12 post #92. Yes, you would have no problems going with 2 suctions. I think that would actually be wise. If I decide to go with a closed loop I would do it much differently than I have ever actually seen. I wouldn't discharge through nozzles at all. I would create a discharge header using furniture grade PVC with holes drilled in it across the length. I would do at least 3 suctions on the other end of the tank. It would work like a gyre on steroids.

I may not have been clear enough. I would put 3 suctions on one side with a discharge header on the other. To make a second closed loop I would reverse the discharge and suctions to opposite sides. I didn't mean to imply going back to front in the tank. Not that it isn't an interesting concept.... ;Bookworm

I think it would be awesome to get the nice linear flow one direction, turn the pump off, start the other one, and get linear flow the other way. Maybe for part of the day have them oppose each other at varying speeds to try and simulate waves along a beach. So many possibilities!

 

[Upstartreefer]

3 suctions on one side with a discharge header on the other

@Brew12 you were clear I wasn't. lol that is the way I will try running the closed loop and see how it goes.

Thanks

 

[mcarroll]

Think tide simulation.....nice flow one way for a few hours, the nice flow in the opposite direction for a few hours.