Bidirectional tidal flow
 

Hello,

Would it be possible to set up a water flow pattern where I could have the main tank water flow in one direction for 5 hours, off for 1 hour then reverse direction and repeat?
I'm wondering if there is a set up with an Oceans Motions unit along with some timers that would accomplish this.

Thanks,
Mitch

Not sure about the OM's but as long as you could have the motor turn very very slowly I suppose it could work. I wonder if it would just be easier to use some Tunzes or Vortechs and work with the controlling options to alternate gyres on a 6 hour cycle. Or just two separate closed loops with different inputs/outputs on each end. Actually considering the recent advent of controllable pumps (Red Dragon? I think? I dunno I'll have to dig up the reefbuilders/reeftools/where-ever-I-read-it link if you need more info), I think this last option could have the most merit because instead of having the the pump "off" on the slack part of the cycle, it could just be at 10% and thus avoiding stagnant buildup or critters seeking haven near the inactive bulkheads and so on.

Pretty common setup, it's typically done with two separate closed loop systems. One CL system with the output on one side of the tank and the input on the opposite side. The second CL system is the exact opposite. Put them on separate timers and set them however you want. You could do it with a single system and pump but you'd have to use special solenoid valves which will cost more than the additional pump and plumbing. The OM won't give you exactly what you're looking for.

Hi Tony,
Thanks. Powerheads would be the easiest route, but at $800 per Vortech, of which I would need two (1" acrylic walls), I would rather try to incorporate it into either a closed loop setup or from the sump return.
If it was from the sump return I would need to either have the sump height at a level high enough to reduce drainback or have holes drilled in the supply tubes to prevent drainback to a lower level sump.
Right now I have my tank drilled for 4 1" seaswirls and I could eliminate 2 for this bidirectional flow idea.


sphelps,
I would prefer to keep the upper water layer moving with the seaswirls with less current at the mid and lowest level.

On Oceans Motions website they say they do some custom work, so I thought I would inquire.

Mitch

Do you have a specific solenoid and valve in mind?
I'm using Reeflo Dart Supergolds that are $500.

Thanks,
Mitch

Yeah the solenoid valves would be more than that. I don't recall the brands but I've priced them out before for a customer and they we're fairly ridiculous because of the size and material needed to be aquarium safe.

A few years back I looked into the possibility of creating this kind of flow but using one pump. It was before OM was around. What I thought about using was a MOV (motor operated valve - electric in this case, although you can get pneumatic-activated as well) on a 3 way mixing valve. The trick is having the right ball in the valve so that as one side begins to close, the other begins to open so that the total flow through the valve remains constant at all times.

The reason I didn't pursue it was the cost of the MOV's was too prohibitive for me. I forget exactly where they were landing in price point specifically but I do recall thinking I would have done it if I could have found one for $200ish so I think it was well above that. The pneumatic ones were cheaper but then who wants to have a compressor going all the time and "psshhhhh!! psssssh!!! psssshhhhh!!" going on all the time in the tank room.

Yeah and to use one pump you'll need at least 4 of those valves. A second pump with some additional holes and plumbing will be easier, cheaper and more reliable.

LOL.

It sounds like it might boil down to another reeflo pump.
Now I need to find out how they stand up to constantly turning on and off.

I did find a 2" solenoid w/valve on the 'net, for a measly $2200.00.

Mitch

Don't know about prices, but here is a little info. from sequence:

http://www.mdminc.com/Doc/Sequence%2...ata_Sheets.pdf

Yeah that will be your best bet. Turning on and off with the duty cycle you're proposing will be fine. The pumps are basically the same as those used in hot tubs which turn on and off way more than that.

Yeah and don't forget to multiple that number by at least 4 as that's the minimum number you'll need for the system if running a single pump. OM may do custom work as well but I can't see how one of those systems, customized or not, will work for you. They just use timing motors to rotate drums and syncing a bunch of them to work together the way you want will be impossible. Unless you had a common suction and two different outputs on each side of the tank with a drum that rotates to the two outputs. You'll still need some kind of timer to turn the motor on and off to provide the pattern you're looking for and to get it right it will also need limit switches to keep track of the drum position. Even if OM would do this the cost would be way more than $500.

You can buy an $8 reed switch, sense the position of the drum then hook that to an Areotronics timer, select the time delay and you are done like dinner. net cost $39 .

Codfather, thanks!

golf nut,

So I would use a 2-way OM unit?
What is a reed switch and Areotronics timer?

Thanks,
Mitch

A reed switch works on magnetism, same type of switch you'd find on windows and doors for alarms. Problem is the OM has a thick plastic casing and you'd need pretty powerful switch to work properly and you would have to enclose one end within the drum which offers will space. Plus you'd need two switches for the two positions meaning you'll also need a smart relay to understand the two switches and control the system accordingly. It's certainly not as simple as described and the cost would be beyond $39.

Not to mention the OM drum is driven by powerful magnets, I can't see a reed switch working properly to begin with.

If you just tee off your closed loop pump and have a valve on either side of the tee why do you need 4? Are you concerned about valving off inlets on either side too? If the inlets were more or less centered why not use just 2 valves?

I think a guy on RC bought a morized butterfly valve or something like that by Hayward. They're pricey but from what I read the pricey ones are extremely reliable.

Overall likely cheaper to use a pair of DC controlled pump for each side. Red Dragon is apparently releasing new pumps as the previous generation had issues. I've heard good things about similar pump but can't quite recall the maker or the name sorry.

How did I edit your post?

If you are only switching every 5 hours they will work fine, the rapid sequencing is their downfall.

If you had a common suction 2 valves would work. I think ideally to create the cross flow you need a suction on one side and the output on the other so in this case you would need 4, which is what I was talking about.

Maybe because we're in the Vendor forum?


Mitch

Monsieur MitchM wants 2 directions only, which means he needs one sensor and 2 magnets 180 degrees apart, the timer falls off, the motor turns, the sensor sees the magnet and the timer turns on again, he can drop a small cam onto the upper mag unit if he wishes and install a micro switch in the underside of the motor mount, there are many ways to do it.

Here we go:

Abyzz pumps by Venotec.

http://www.korallenzucht-wendel.de/g...n/venotec.html

http://www.youtube.com/watch?v=wFGASFHEWL8

haha, get that out of there! I can't remove it :lol:

BTW that still wouldn't work as simply as you think. Once the switch makes contact and shuts off the movement what then tells it to move on? You still need a smart relay. And you can't run a cam, is it not sealed to prevent water leakage, it would think it would have to be magnetism which wouldn't react properly with the magnets already present.

Oh shoot didn't realize we were in a vendor forum. Not sure my links are appropriate here. Also forgot golfnut = paul lol.

"He" has a name you know......





:lol:
(sorry, couldn't say that with a straight face for long...)


Mitch

It is running on my desk as we speak :)

I am sensing the motor shaft which is directly related to the magnets on the other side of the membrane.

So how does it work with a smart relay?? I think you'll have to post a video.

I will try to get some time and capture it, it works with the $39 parts I posted earlier.

Describe works. I mean does it work by itself or do you have to put input into to it. I'm curious how the system will work without some kind algorithm, once the switch is triggered and it turns off the motor how exactly is this reset so it can continue until it hits the next switch?

It's a count down timer, when the motor turns and a magnet effects the sensor the power triggers the timer to start counting down and turn the motor off, once time down has occurred power goes to the motor, it turns and when the next magnet is seen it repeats, you can time down anywhere from seconds to weeks depending on the timer used.

My apologies... fixed!

I am actualy planning this for my next tank.. I have been looking into it for about 4 years now. you need two valves, one pump and a bunch of plumbing to do it right. this also includes drilling both ends of the tank with several holes.

what I am planning is about 6- 1" bulkheads on each end which combine into a manafold on each end. then 2" line splitting to two actuated valves one on the suction side and one on the discharge side of the pump.

with this set up you will actualy get complete lamaner flow across the whole tank so when in operation the bulkheads on one end are the discharge and the ones on the other end are the suction, when the ballvalves change this suction and discharge change ends.

this is the ball valve if you notice the one configeration has no "off" so during change over water flowes through both outlets.
http://www.haywardflowcontrol.com/pd...Way_Valves.pdf

here is the actuator
http://smsnet1.smsmktg.com/~hayward/...s_Actuator.pdf

the only other thing to do would be to come up with a controler that would alternat power on a timed basis to open one as it closes the other, then after a set time reverse the process. this could be done with an adruno based micro processor or what ever.

Steve

Ok I'm still missing something here. It must be more than just a count down timer. If this were the case the drum would rotate until the sensor is triggered and opens a circuit. The open circuit triggers the counter which turns off the motor. OK so far so good but then when the counter stops the sensor is still in the same position and therefore the circuit is still open which will reset the timer. This will continue forever and the drum will never move again. For this system to work that timer must have some kind of algorithm built in, which will either be a delay or something that over rides the sensor until the circuit closes again.

For the system to be reliable a simple a delay won't work. If it's an over ride that's a pretty cool little system. How much would the whole system cost, built and ready to go?

Steve,

How are you going to deal with stuff getting drawn into the suction bulkheads if you're using the same ones for discharge?


Mitch

That's what I did 8 years ago with the tsunami device, with just one valve.

http://www.youtube.com/watch?v=rCgLY0baPOk

It would be a fairly easy DIY mod to a 4 way or 2 way, still will cost $39 :)

If the OM drum needs only to rotate 90deg to open the opposing ports then you could easily calculate the RPM of the OM valve.
Lets say 2rpm that means every 15sec 90deg is achived.
Theirfore if you have a adiquite timer you could eaisly switch power off for 6hrs then turn power on for a period of time which would be chosen bye increments of time such as 15sec (90deg), 45sec (180deg) ,1:15 (270deg) ect.(creating random flow to simulate the changing of the tide) then close the power to the OM to have the flow comming out of the other ports
make sence?

The problem with that is that if you are off by 1 degree or a couple of seconds, it would only take a few days before you would have be off your cycle and have flow coming out of both outlets before it went back into sync again.:smile:

Mitch

Finding a cheap reliable multi-function timer is the issue, you may as well go directly to PLC do not pass go and do not collect 200 dollars, the OM revolves at 1rpm, it may take a little time to program it correctly guessing time per degrees, I wouldn't even waste my time, set it for 15 sec intervals and then eventually it will repeat its self every 4 years:)

you are better off with a positioning sensor to be accurate.

Does the 2-way come in a 2" size?

Monsieur Mitch