MitchM tank build

[mr.wilson]

Sorry, if I'm making an already confusing discussion, even more so, but I have a few questions about your design. There are four holes in the top for the (now two) Seaswirls, but the plumbing is coming up from within the tank?

The Supergold Darts only have 12' head before shut-off so I assume you have 1.5" plumbing all the way up, and you aren't going more than 6' up. That 4300 GPH quickly turns into 2200GPH with 6' of head, a ball valve, check valve, and a few elbows. If the two Seaswirls are on a closed loop they will also have more headloss than your proposed tidal system. How many effluent lines will you have on your closed loop? I assume you are dropping down to 1" at the Seaswirls. You may only have 1500GPH on your closed loop by the time you finish up.

You may want to consider a pressure rated sump return pump like a Blueline or Iwaki 100 for the two Seaswirls and use four 1.5" effluent lines (reduced to 1" at the tank) for each of the two Superdart closed loops.

One of the benefits of an OM unit over solenoids (other than cost and noise), is that the OM will allow some passive flow through the closed line(s). This is beneficial considering that these lines will be off for 5 hours and will become anaerobic. Also keep in mind that you may have some air in the lines as they fire back up again. The bubbles aren't a big problem for corals or fish, but they do make a mess of your lighting (salt spray). The Om unit will not allow air into the line when it is cycled "off". The OM has a soft on/off cycle so you don't dislodge biofilms from your plumbing every time it changes path/direction, as you would with an abrupt cycle.

I'm leery of turning pumps on and off on frequent cycles, especially pumps that are not magnetically coupled such as the Sequence line. I find with these pumps, particularly as sump returns, perform and sound differently as the impeller settles in varying positions. If you set it and forget it, these pumps are reliable. Pumps with a soft on/off are another story.

Are you using the check valve as an air intake or to physically stop water flow (back siphon)? Is it a swing, ball or wye style check valve?

I'm not sure if you will achieve your tidal sequence if you are just using one pump to go through the cycle.

[mr.wilson]

The lids will raise the tank temp at least 5˚F. They will limit gas exchange slightly, but it isn't a major concern. You will get condensation and salt creep/spray and the lids will become cloudy further diffusing light. If you are using metal halide lighting, the lids will warp considerably. Flipping them weekly helps keep them straight.

[lastlight]

Lol not recommending a pair of Abyzz with a controller just yet Mr. W? It's certainly not a cheap option.

That's how I'd do it. You could run them 100,10... 10,100 so the lines don't go stagnant.

[mr.wilson]

Originally Posted by lastlight

Lol not recommending a pair of Abyzz with a controller just yet Mr. W? It's certainly not a cheap option.

That's how I'd do it. You could run them 100,10... 10,100 so the lines don't go stagnant.

Trouble maker!

Yes, I would use two Abyzz 420 pumps with a controller and call it a day ($4,800.00). You would do fine with two Abyzz 200s or even one if you tune it right. A couple $25 Eductors make it even more fun

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

[MitchM]

Sorry, I don't care for the short mechanical wave action and I'm aiming for a more sustained water velocity of 15cm/sec in the mid and lower zones.

[mr.wilson]

The wave video is just a gimmick to show the possibilities. I don't care for the waves either. You can use two pumps on the controller as a closed loop, return pump or drop them right in the tank. You can run them at 5% to keep water moving through the pipe and at the opposing end, run one at 100% for your five hour tidal flow.

[golf nut]

Originally Posted by MitchM

Sorry, I don't care for the short mechanical wave action and I'm aiming for a more sustained water velocity of 15cm/sec in the mid and lower zones.

I agree 100% it wasn't designed to do that, just to show how using inlets and outlets correctly can greatly increase the flow potential, and to show that you do not need a dirty great big box in the tank to get far more movement than a wave box could ever achieve.

[MitchM]

Originally Posted by golf nut

I agree 100% it wasn't designed to do that, just to show how using inlets and outlets correctly can greatly increase the flow potential, and to show that you do not need a dirty great big box in the tank to get far more movement than a wave box could ever achieve.

Plus the point that already having a Profilux the last thing I want to add is another controller.
They sound like great pumps.
I wonder if a Profilux could accomplish the same timing for someone that would want that type of water movement?

[MitchM]

Originally Posted by mr.wilson

The lids will raise the tank temp at least 5˚F. They will limit gas exchange slightly, but it isn't a major concern. You will get condensation and salt creep/spray and the lids will become cloudy further diffusing light. If you are using metal halide lighting, the lids will warp considerably. Flipping them weekly helps keep them straight.

The lids are Lexan, so I am not expecting much, if any warpage.

[mr.wilson]

Paul's adaptation of his Revolutions product to an inline solution for you is nothing short of pure genius. His best ideas are inspired from specialized requirements like yours.

Lexan will still warp. I have used lots of these lids over the years.

Remember those are the Seaswirl flow limits, not the limits of the Dart to push water through a Seaswirl.

I did a 600 gallon acrylic tank (96x30x48) a few years ago, using two darts on 2 OM 4ways, with a Blueline 100 return pump. Flow was excellent. Use an online head loss calculator to make sue you are getting the best out of your system.

Use threaded parts where you can so it is easier to adapt to change.