Newbie - Can someone explain about closed loops?

[Aneille]

What do closed loops do exactly and why do you need it? And what are the alternatives to setting your tank up that way?

Thanks,

Kim

 

[mountainbiker619]

closed loop is used to provide more water circulation inside of the aquarium, without the use of power heads thus providing a clean uncluttered aquarium.
Below is a picture of the plumbing on my 60. The far right bulkhead fitting is the intake of my closed loop. The water is taken from the tank and goes down to a pump and then is returned to the tank via the two middle bulk head fittings. On the inside of the two closed loop returns are four adjustable sprayers (two on each bulkhead fitting). With these a can adjust the water flow direction to any direction I desire.

 

[Aneille]

Funny that you replied because it was your tank pic that got me wondering what they did. I mean I understood it was for circulation but couldn't figure it all out!

I guess my next question is if I am getting a tank, should I have a closed loop system in mind and have the back of the tank drilled for it? Or do the powerheads work just as well & it simply is a matter of the clutter in the tank? Is the cost of the hole drills worth it?

The tank will be a 120 or a 180 gallon.

Thanks,

Kim

 

[Len]

Hey Kim,

Welcome to Reefs.org!

Closed loops are better then large powerheads for several reasons. Obvious one is the clutter in the tank. Closed loops can also provide a lot more circulation then any powerhead combination could. In addition, if you're using the right pump, closed loops will transfer less heat to the tank then mutliple submerged powerheads of comparable flowrates. Closed loops can also move more volume of water with less water velocity .... an equation that makes for best water circulation in a reef tank. What else? Most inline pumps are more reliable then powerheads. And some people don't like powerheads because of possible stray electricity from submerged electronics. There's probably lots more, but that's what I can think of right now But most importantly, closed loops look so much cooler

 

[Len]

BTW, there are a couple of good closed loop threads referenced in the FAQs (one of the top announcements). they're good reading. You can also search the board for "closed loop" (make sure "search for all terms" is selected). And of course, you can ask it here

 

[mountainbiker619]

Kim,

I made a detailed drawing on paper as to the exact places I wanted the holes, and notes for what size bulkhead fitting. I then had my LFS fax this drawing off to the aquarium maker and they made it exactly to my wishes. Each hole drilled cost $10.00's each. Each of the back bulkhead fittings are 3/4 inch. I am getting ready to build a 100 gallon system to the same way I have this 60 done. One major lesson learned from the 60 is to make sure the closed loop intake fitting is bigger. Reason for this is for less suction. I have already lost an Anenome due to it getting sucked into the strainer. On the 100 I plan on making this fitting for 1 1/2 inchs vice 3/4 I have on the 60. For me the extra few pennies spent on the closed loop in very much worth it.

 

[Aneille]

I thought I understood it but know after thinking about it overnight I am a little unsure. I read the FAQ's and it got me thinking too much!

With a closed loop do you need any powerheads? Do you still use something like a Wavemaster Pro to regulate the circulation?

And finally for a larger tank would I have to drill more holes for output so there is better coverage?

My other concern is since I have never set up a reef, how will a newbie like me know where to place the output holes so they aren't in the way of rock etc but will provide the circulation I want (but since I am new, I don't know where I need it most?)

And lastly is there anyway to get a "whoosh" effect every once and awhile just because it is cool! Unless even once and awhile it would really hurt my corals!

Thanks,

Kim

 

[Aneille]

I must have been tired last night because I re-read some of the FAQ's and I answered some of my own questions.

But I still have questions about the #of holes I would need and how will I know where to place them?

Also still wondering about the "whoosh" effect.

Thanks again!

 

[wade1]

Hole placement is based on live rock structure and size of tank. One of my main objectives with placement is to provide the most random flow possible, while exchanging alot of water from bottom to top of the tank. Also, you need to keep the intakes (you will have to put screens on them) accessible to be readily cleaned, so that sometimes limits placement options.

Best loops I have seen typically draw from lower in the tank (usually on the back behind live rock piles) and either emerge near the top or aim up and forward at a slight angle.

As for a wavemaker, you cannot use them with real pumps, however, I have 3 loops on my system and 2 of those are on appliance timers that turn them on and off. One is on during daylight hours (12 hours) and one alternates on and off each hour. It does wear on the pump to be turned on and off alot though.

Wade

 

[Aneille]

Thanks for taking the time to respond to my questions, everyone has been very helpful.

Anyone out there that uses closed loops and have pics that would be great. I'd like to see a bunch before I determine where I should even be thinking of putting mine.

Thanks,

Kim

 

[gcantu]

What about a power outtage? What happens when the power goes out suddenly? Since the drain is below water level, will excess water keep draining or what? How does this system keep the rest of the water from draining onto the floor?

 

[mountainbiker619]

Kim,

Another lesson learned that I just thought of is to make sure the closed loop intake is about 6 inches below the water line. My intake is about 3 inches below the water line and due to the high suction generated due to the 3/4 inch hole, it sometimes created a water tornado thus sucking air into the closed loop and on the return side is a massave amount of air bubles. Here is a link to a friend of mine that shows how he did his closed loop (notice the AWSOME plumbing design )

http://www.crownsoftware.net/Aquarium/


gcantu,

A closed loop is completely closed. So if you lose power to the pump you will have no water spillage onto the floor. Fill up your sink with water, then grab a power head and attach to it about 3 feet of hose. Place the powerhead in the sink that is full of water. Now turn the powerhead on and place the open end of the hose about an inch below the water line in the sink that is full of water. You have just created a closed loop.

 

[Aneille]

Thanks again for your response. In that example you gave me of a closed loop there are no holes drilled. Doing some plumbing like that may be my best bet, although that was some serious plumbing.

I am nervous about drilling holes in my tank when I am doubtlful I will be sure where to place them.

Thanks so much for that link. I am sure it will aid me a ton when I go to set this thing up!

~Kim

 

[mountainbiker619]

Kim,

Its my pleasure Be sure when you start glueing the pvc together that you go crazy with the glue. In the ending it may not look pretty due to grey/purple glue everywhere..but it will assure water and air tight fit.