Are "closed loop" systems old school?

[Av8bluewater]

What most people fail to consider is that modern propeller pumps are a much more energy efficient option.

Ignoring all the fancy options, for a straight up comparison look at a CL vs a basic propeller pump of similar rating:

Option A: One Reeflo Dart producing 3600 gph uses 165W on average and costs $315.

Option B: One Tunze 6125 producing 3150 gph uses 22W and costs $243.

So, for roughly the same flow (give or take plumbing) the CL would cost more to set up ($315 plus bulkheads & valves vs $243 and just installing it) plus it uses 7.5 TIMES the electricity. The Tunze would cost ~$20 in electricity per year depending on local rates. The CL would cost $144 per year to run. At that pace, you save enough money to buy a second Tunze in two years vs running the CL.

There are other reasons why CL have gone out of style but as far as I can determine, the economics of the setup are the single biggest factor.

HTH,

Not only that but if you split up the CL from one Dart .. all the bends in elbows, loc lines, height up to the tank and then a pointy narrow exhaust just isn't the same amount of flow. I haven't figured it up but I'm sure you're not getting anywhere near 3600 gph by the time it gets in the tank.

Also... a big item: if it comes time to sell the tank it could be a problem. I'm considering a 230 gallon tank right now that the only thing that bothers me is a drilled hole in the bottom. Can seal it up I guess. Tank is custom made and brand new that owner decided he is not going to set up. If one ends up selling a CL tank and you have to part things out it could be too specialized for many.

 

[ganjero]

As everyone pointed out the newer PH are a better option for circulation. CL used to be popular and a better option when propeller style (specially DC) pumps were non-existent and you had to fill your tank with a bunch of impeller pumps like maxijets, aquaclear and really old tunzes.

Since some made the reference and comparison of GPH, you must remember that the external pumps ratings are more accurate than the ratings for propeller style pumps like Tunze, Vortechs, Jebaos, etc., which are are mostly guessestimates.

 

[Jwill1212]

Been running closed loops for years.......(15 plus) never had an issue with leaks or floods.......If designed right, they are great, especially with the new DC pumps. All intakes and returns are concealed with the rockwork. To me, a "vortec" or similar is for glass tanks or special flow requirements that develop after the tank is built.........

 

[rlpardue]

Closed loops require extensive planning to do properly. Research options such as "over-the-top" outputs with locline, intake bulkhead placement, etc. I run a Dart/OM 4-way closed loop, have one MP40 and one WP40. I like each of them for different reasons.

The Vortech and WP40 are nice because they really get the bulk of the tank water moving. The CL is nice because I have multiple locline outputs that I can adjust to hit dead spots. (Yes, with a Vortech you will still have dead spots).

 

[saf1]

It all comes down to design and quality. If it is done right then it will be problem free. Same with anything you put into your tank. Just one mans opinion.

Has far has old school? How old was the person you spoke to at the store? They only push product and rarely give accurate advise. Some do, but I think at the end of the day they only care about the dollar and pushing product. You can read any number of threads here when people buy something then ask for help then say their store told them it was ok, etc.

If you want to see old school there is a thread on the general forums here that talks lists old school and DIY stuff people have done. Standard lights are old school has are fluorescent yet people kept tanks with them. LED's are the rage yet people are still using T5's and MH. Need I go into sunrise and sunset options with controllers, etc?

One thing this hobby has taught me over the years is that patience pays off in the end. Tolerance, restraint, self-restraint; however you want to word it but at the end of the day when you add patience has you build and maintain your tank you mitigate risk and failure points.

Oh, old school? People are using solar panels now to offset the crazy cost of our tanks. :inlove: Just saying

 

[usmc121581]

but in reality they tend to have frequent issues.

Dont know who you know that has frequent issues with there CL system, but they may want to redesign it. My CL system has run flawlessly for 5+ years. Only issue was a pump seal. replaced and working like a champ.

 

[Aquatron]

I have had two 300 gallon DTs with close loop and a 750 gallon DT using close loop and never had a problem.......knock on wood I enjoy tinkering with my systems and building things so planning and installing a close loop system on my builds to me is a joy.
If you know what your doing then close loops are great if you don't then you give all the reasons stated above

 

[mussel and hate]

Closed loops aren't old school, air lifts... now that's old school.

Closed loops are great if you want to move water across the tank. If you just want to create localized turbulence than a submersible propeller pump or a Vortech is suitable.

If you're going to drill the tank for an overflow then you may as well drill for a closed loop. If you can trust the overflow bulkhead seal then you can trust your closed loop bulkhead seals as well, they aren't any different. It'd be like putting only one window on your house to reduce point of entry for burglars. People here come up with some wacky rationalizations.

 

[planedoc]

Rocket engineer and av8bluewater are right on the money.
Bottom line is cost wise CL are far more expensive to operate than other options. After head loss it cost about 10 X more in electricity to move water through a CL vs an intake pump. If you don't want to see powerheads in your tank and an extra $10 + a month in electricity doesn't bother you than you can actually build a better circulation system with a CL than you can with in tank pumps. Being able to pump water in and suck water out where ever you want can create better flow patterns than powerhead type device can. There is the safety factor of more joints and more holes in the tank but if done correctly that is really not an issue.
To me it's simple economics.

 

[Aquatron]

Let see my 300 gallon tank using two MP60s x $ 775.00 each = 1,550.00
300 gallon tank using four Laguna 2400 pumps x $ 135.00 each = $ 540.00
Plumbing including gate valves/bulkheads $ 200.00
-----------------
Difference of $ 810.00
400 watts(Laguna 100 watt each x 4) x 24 hrs per day = 9,600 watts per day x 30 = 288,000 watts per month. 288,000 > by 1000 KW = 288 x .13 = $ 37.44 per month to run pumps one month.
$ 810.00
> 37.44
---------------
21.63 months
My close loop using four pumps only runs one pump at night when lights go off so I am only using 100 watts not 400 at night so it would take several years of using my close loop just to pay for the MP60s +-.

 

[RocketEngineer]

Let see my 300 gallon tank using two MP60s x $ 775.00 each = 1,550.00
300 gallon tank using four Laguna 2400 pumps x $ 135.00 each = $ 540.00
Plumbing including gate valves/bulkheads $ 200.00
-----------------
Difference of $ 810.00
400 watts(Laguna 100 watt each x 4) x 24 hrs per day = 9,600 watts per day x 30 = 288,000 watts per month. 288,000 > by 1000 KW = 288 x .13 = $ 37.44 per month to run pumps one month.
$ 810.00
> 37.44
---------------
21.63 months
My close loop using four pumps only runs one pump at night when lights go off so I am only using 100 watts not 400 at night so it would take several years of using my close loop just to pay for the MP60s +-.

Is the Laguna pump controllable? Does it change flow rates? NO.

Folks need to be smart about this and not compare apples to oranges. CL pumps typically do not change flow rates nor are they computer controlled or wirelessly synced. Each of these features costs money. A CL not employing these features isn't a valid comparison to a Vortech pump that is one of the most "techy" pumps on the market.

Instead you need to look at a pump supplying the same constant flow rate. And if you run the numbers, a CL is likely to be more expensive over the long haul.

If folks want to go with the expensive option, that is always their choice. This goes for CL as well as powerheads. Each has their benefits and drawbacks, and it is up to each of us to choose the path we want to take. But please, if you are going to argue numbers don't try to inflate them by using the most expensive components you can find when the less expensive options will do the job equally well.

Disclosure: I own (2) MP10wes and (1) MP40wes. However, I started my setup with a pair of MJ900s with propeller retrofit kits. It's all about what works vs how much you want to spend.

 

[Aquatron]

Well yes they can be controlled with a gate valve and change flow rates MPs and Close loop are apples and oranges.
Do you think corals and fish really care about "techy" or just about a healthy environment. Yeah I can't do sun rise and sunset but I can have turbulence flow in more than one area and true vortex flow.
Close loop and MPs are a choice and nothing more of two great ways a hobbiest can add flow to their tank.

 

[mussel and hate]

To be fair the OP was about this apples to oranges comparison and whether or not CLs are "oldschool" (and I believe implied was outdated/antiquated).

Folks should be smart and see that a CL moves a given volume of water from point A to point B whereas a submersible propellor pump just blows a fan shaped plume in whatever direction it's pointed. The two are distinct in function. A CL intake behind a deep rock stack will move way more water through the stack than a Vortech pointed at the face or buried within. The Vortech is great for creating turbulent flow in it's direct path.

This isn't an either or proposition. I use both a CL and a Vortech pump. If controllable external DC pumps been available at a reasonable price a year ago I might have skipped the Vortech. What sort of motor drives the pump that is plumbed to the CL determines the sort of control you have, that and the switching logic anyway.

 

[ReefKeeper64]

I love my closed loop!

 

[mhsmith]

I don't think anyone getting into this hobby is overly concerned about the finances. Last I checked this is one of the more expensive hobbies out there. I love it, but with all the electricity used with chillers, lights, pumps, granted we would like to decrease the costs, but I don't think that is what is driving this conversation between closed loops and not. Maybe it's a factor, but the difference between visible pumps in the display tank and not is probably a bigger issue than saving $10 a month. Maybe I'm wrong. I'm sure they're will be comments.

 

[ca1ore]

Like I said earlier, in-tank flow-pumps and external close loops simply fill a different function in today's reef tank. Certainly in the distant past we used closed loops for in-tank surge, but they didn't work all that well for that, and we saw a profusion of devices (Oceansmotions, sea swirls, etc.) that IMO failed to really address the issues - plus they are expensive to run. Then Tunze and others came out with propeller 'stream' pumps that did a FAR BETTER job of in-tank flow and relegated the closed loop to a relic of the past ... or did they? As it turns out, propeller pumps don't always do a good job of moving water behind the rockwork (unless you prefer and use a very open rock structure) but closed loops do! So that becomes their role. To dismiss them as 'old school' is to fail to recognize the role that they can play as a tool for the reef tank.

 

[ReefKeeper64]

I agree with you about the finances. I use a reeflo pump and it creates tons of water flow while only using 100watts of power. With all the other costs involved in owning a reef tank, this isn't a concern of mine.

 

[mhsmith]

Reefkeeper, I may have to steal your plumbing design. I am going to do a similar application, except I have purchased the Flowwolf instead of the Ocean Motions. I don't know how it will compare, not having experience in either, but I'm going to give it a go in my new tank design. THanks!

 

[Dmorty217]

Rocket engineer and av8bluewater are right on the money.
Bottom line is cost wise CL are far more expensive to operate than other options. After head loss it cost about 10 X more in electricity to move water through a CL vs an intake pump. If you don't want to see powerheads in your tank and an extra $10 + a month in electricity doesn't bother you than you can actually build a better circulation system with a CL than you can with in tank pumps. Being able to pump water in and suck water out where ever you want can create better flow patterns than powerhead type device can. There is the safety factor of more joints and more holes in the tank but if done correctly that is really not an issue.
To me it's simple economics.

They aren't far more expensive to operate, but sacrifices have to be made if you want the clean look of a CL system as opposed to have power heads everywhere in the tank. There is "head loss" in a closed loop system because it is all contained and the pump is on a closed loop hence the name. Bottom line is if you have a big tank and want some flow there are no other alternatives to a CL. I'm willing to bet my CL system has more flow then any tank out there with power heads in it, even if it does cost me 25$ a month more

 

[Dmorty217]

There isn't "head loss"