...continued from the
Bidirectional flow thread


(****Post from Kevin at Red Coral)


There are 4 holes drilled in the top brace to accommodate 4 seaswirls,

****1.5" bulkheads

which were to be fed by the 4 holes drilled in the lower bottom back of the tank.

**** I can't tell the size of these holes I would hope they are for 2" Bulkheads

My original sump return was to be determined and because the tank is acrylic I have the ability to reasonable modify it.

**** You can modify as acrylic is easy to drill but with such an incredible tank (do you want to?)

What I would like to do is use only the front two top holes for the seaswirls and drop a couple supply pipes originating from the sump down the back two top holes.

**** seaswirls are an option.

The two supply pipes would alternate the flow, clockwise or counter clockwise in 5 hours one direction with a 1 hour rest followed by 5 hours in the opposite direction, 1 hour rest. Repeat.

**** I personally do not recommend creating the directional flow from your supply lines from your sump..This is where your heaters, filtering etc. are located and do you want to shut that down for an hour every 5 hours. Your directional flow pattern is also where it could become problematic. Do you really want or need to create this flow supply from the sump?


The top zone would be kept moving through the closed loop full time.
I have 1 reeflo dart supergold for the closed loop and 1 reeflo dart supergold for the sump return.

Depending on the results of the final setup, I was leaving open the option of adding the MP60's. The price of them is giving me a lot of incentive to minimize how many (if any) I put in there.

**** If the 4 closed loop holes in the lower back are 2" bulkheads you could then add another dart gold and use 2 of these each to supply a pump and each return would be to one side of the tank. You could pipe in whatever flow and to what areas you wanted. Then with timers you could create your directional flow at the 5/ 1/ 5 timing.

****Kevin

Hi Kevin,

The holes in the top are 2 1/4", the holes in the back are 2 1/2".

That's a good point about the heaters. I wonder how much heat the tank would lose? I heard that acrylic had some insulating properties, plus I'll also be using lids on the tank.
I'm not too concerned about the temporary loss of filtering at this point. I don't want a heavily stocked tank. The tank feedings could occur near the end of the rest cycle.

If I went with your last setup suggestion, I would still need to drill a couple of holes for the sump return, wouldn't I?

Hey Mitch you should get the ECO Reef Rock and do the dry structures that is what Im doing with my 96footer too. i love the rock easy to work with and alot better and then you can take your time with it...:wink:

Hi Mike,

That's what I was going to be doing with the base layer - then I was going to drill and peg my existing LR onto that.:smile:
If I need more after that, I'll most likely get more Eco Reef Rock.

.

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.

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.

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.

Hi Mr. Wilson,

Thanks for your input, I've been following your work on RC.:smile:
The original design was to have closed loops with two Dart pumps. Each pump would have 2 of the rear intakes and supply 2 of the seaswirls. The pumps were to be mounted on the back of the stand itself just below the level of the tank. This mounting would be similar to the mounting of the closed loop pumps on the Penn State main display tank. As it is a closed loop system, head loss would be minimized and friction would be minimized by keeping the actual plumbing run as short as possible.
When I ordered the tank I had not determined the sump return and had intended on drilling the tank as needed for that.

At this point I am going to be using only the front two seaswirls and dropping two supply pipes from the sump down the two rear holes that were originally going to hold the two rear seaswirls. That means that I will have the 4 rear intakes for 1 Dart pump supplying the two front seaswirls.

There are no check valves in my design. I have not had good experiences with them in the past.

As the system sits now, 1 dart pump will be supplying close to the limit of 2 seaswirls rated GPH.


The cycle planned is actually 5 hours on, 1 hour off. The outlets for the sump return will be designed to allow for drainback of the water to the sump, so there will be no water remaining in the plumbing lines. There will be air coming back through the lines, but given the closed top of the aquarium, the lights will not be affected. I'm not sure what the effect will be from any biofilm being dislodged on a regular basis from the plumbing.


The effect of the on/off cycles are a concern of mine with the Dart pump and I am open to changing to a different pump for that application.

Again, I will not be using a check valve. The back siphon will be allowed to happen.


My original post to Oceans Motions was to see if they could come up with a design that could accomplish just that. Paul at OM thinks he has a non-solenoid controlled design, and I am waiting to hear back on the final results:smile:

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