Karim's 1500gal dream reef
- Thread starter karimwassef
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karimwassef
Active member
For circulation, the ease, control, space, power and cost of powerheads is much better. This uses 48 WP60s ~ $4000 with a combined flow of 250,000 gph. Essentially that's the power of a personal submarine for the cost of a seadoo (even thought of that as an option
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karimwassef
Active member
Each of the 48 DC powerheads is controllable so I can use array flow shaping too.
karimwassef
Active member
I have a new idea and I thought I'd throw it out here and see what you guys think...
I've always wanted to try a tide emulator that changes the water level in the tank over time. This is almost impossible in most tanks, but this one has a "floating overflow" ... "almost".
The current incarnation has the overflow sitting on top of glass legs that support it and go down to the false floor. realistically though, the overflow compartment can be supported by the PVC pipes alone. The glass below it is really for channeling the flow from the powerheads into the separate sections of the tank (to avoid short circuit flow loops). The glass feet can be lowered by a few inches and the overflow chamber can be separated from the back wall allow it to free float on top of the PVC pipes... think of an offshore oil rig floating on the ocean with adjustable pedestals.
Now, the overflow chamber can be raised or lowered if the PVC pipes were repair extensions
That would give the overflow 6" of play up and down.
I haven't figured out how to connect the overflow chamber to the backroom for actuation (without interfering with the maintenance area of the powerhead chambers) but those are engineering problems to solve.
I plan on having most of the rockwork no higher than 6" off the ground (based on experience with my current tank), or potentially having almost no rockwork at all to provide enough space for the corals to grow. with 18" to the top of the tank, that gives 12" of remaining coral growth height. I could use the actuated overflow height to modulate about 3".
In fact, during a surge, I can intentionally synchronize the overflow to drop in expectation of a coming surge to limit the potential of an accidental overflow.
Extending on that idea.. it's possible to set up waves of surface flow in the tank just by moving the overflow up and down creating a divergent flow pattern to the center of the display.
This solves another problem I was struggling with on the powerhead channel flow... namely that it's flow in only one direction (down the tank length). The cross flow in each of the channels is limited to the returns from the main loop (which is not nearely as high in flow). I had alternating jets to make up, but it wasn't satisfying... By adding the ability to create accelerated flow into the overflow chamber by lowering it, I now have the cross-flow directional flow without adding more powerheads.
Thoughts?
I've always wanted to try a tide emulator that changes the water level in the tank over time. This is almost impossible in most tanks, but this one has a "floating overflow" ... "almost".
The current incarnation has the overflow sitting on top of glass legs that support it and go down to the false floor. realistically though, the overflow compartment can be supported by the PVC pipes alone. The glass below it is really for channeling the flow from the powerheads into the separate sections of the tank (to avoid short circuit flow loops). The glass feet can be lowered by a few inches and the overflow chamber can be separated from the back wall allow it to free float on top of the PVC pipes... think of an offshore oil rig floating on the ocean with adjustable pedestals.
Now, the overflow chamber can be raised or lowered if the PVC pipes were repair extensions
That would give the overflow 6" of play up and down.
I haven't figured out how to connect the overflow chamber to the backroom for actuation (without interfering with the maintenance area of the powerhead chambers) but those are engineering problems to solve.
I plan on having most of the rockwork no higher than 6" off the ground (based on experience with my current tank), or potentially having almost no rockwork at all to provide enough space for the corals to grow. with 18" to the top of the tank, that gives 12" of remaining coral growth height. I could use the actuated overflow height to modulate about 3".
In fact, during a surge, I can intentionally synchronize the overflow to drop in expectation of a coming surge to limit the potential of an accidental overflow.
Extending on that idea.. it's possible to set up waves of surface flow in the tank just by moving the overflow up and down creating a divergent flow pattern to the center of the display.
This solves another problem I was struggling with on the powerhead channel flow... namely that it's flow in only one direction (down the tank length). The cross flow in each of the channels is limited to the returns from the main loop (which is not nearely as high in flow). I had alternating jets to make up, but it wasn't satisfying... By adding the ability to create accelerated flow into the overflow chamber by lowering it, I now have the cross-flow directional flow without adding more powerheads.
Thoughts?
JonezNReef
Member
This guy did a really nice build where he had high and low tide. A bit different concept
https://www.manhattanreefs.com/foru...ntertidal-reef-flat-mixed-biotope-system.html
https://www.manhattanreefs.com/foru...ntertidal-reef-flat-mixed-biotope-system.html
karimwassef
Active member
<a href="http://s1062.photobucket.com/user/karimwassef/media/Designs/0_zpszmgdsphz.png.html" target="_blank"><img src="http://i1062.photobucket.com/albums/t496/karimwassef/Designs/0_zpszmgdsphz.png" border="0" alt=" photo 0_zpszmgdsphz.png"/></a>
It's not that there isn't always flow to the overflow anyway. It's just that there's no way to push it into a very high flow mode or modulating it.
There are 6 separate returns to the tank all coming from the surge and controlled by actuators (that can be controlled for flow). Four are in the middle of the corals/rocks and 2 run down the length of the tank sides (8' down) with alternating flow heads every foot or so. That's ok, but suddenly dropping the overflow box by 3" would initiate an immediate surge event that flows from the edges of the tank to the center (divergent flow, actually convergent in this case, but you know what I mean).
To put it in perspective, that's 180 gallons over water that gravity is going to pull down to the sump (yes - resizing the sump...).
If I do that over 30 seconds, that's 720gal/min or >40,000 gph (over 30 seconds + however long it takes to actually drain).
That's more in line with what a surge for this size tank needs and it provides the right directional elements.
It's not that there isn't always flow to the overflow anyway. It's just that there's no way to push it into a very high flow mode or modulating it.
There are 6 separate returns to the tank all coming from the surge and controlled by actuators (that can be controlled for flow). Four are in the middle of the corals/rocks and 2 run down the length of the tank sides (8' down) with alternating flow heads every foot or so. That's ok, but suddenly dropping the overflow box by 3" would initiate an immediate surge event that flows from the edges of the tank to the center (divergent flow, actually convergent in this case, but you know what I mean).
To put it in perspective, that's 180 gallons over water that gravity is going to pull down to the sump (yes - resizing the sump...).
If I do that over 30 seconds, that's 720gal/min or >40,000 gph (over 30 seconds + however long it takes to actually drain).
That's more in line with what a surge for this size tank needs and it provides the right directional elements.
karimwassef
Active member
YES! I remember him. The other thread I had on creating circulating flow referenced his thread as an example of moving large volumes of water. I settled on the powerheads for more programmability and control, but it was great.
He had great videos too. Let me find them and link them in here for inspiration.
karimwassef
Active member
arghh his videos are offline..
karimwassef
Active member
in case you think he's nuts (and me too):
This could be one way to get rid of those pesky parasites that you just can't slough off in the water...
This could be one way to get rid of those pesky parasites that you just can't slough off in the water...
karimwassef
Active member
here's his design.. different (slower to fill and release = more like tidal).
I would use mine for tidal action as well as surge action (depending on rate of change).
I would use mine for tidal action as well as surge action (depending on rate of change).
karimwassef
Active member
on a separate note - I have a request to any fluid flow engineers out there.. I know how to do beam shaping for electromagnetics (radar, wireless, etc...) using arrays of antennae. I was thinking the same thing for the array of powerheads to do "flow shaping" assuming this is a common thing...
so.. I've been searching and found ... nothing.
Hasn't anyone tried doing this before in fluid mechanics? Is the physics so different that it doesn't work at all?
Just try googling "flow shaping using pump arrays"... is it a novel idea?
so.. I've been searching and found ... nothing.
Hasn't anyone tried doing this before in fluid mechanics? Is the physics so different that it doesn't work at all?
Just try googling "flow shaping using pump arrays"... is it a novel idea?
JonezNReef
Member
Heres a cool idea I also ran across
https://www.youtube.com/watch?v=KBJm8uiotiA
https://www.youtube.com/watch?v=KBJm8uiotiA
karimwassef
Active member
The telescoping element will be mostly hidden in the PVC plumbing. The 3" that extend out can be inside if a larger diameter pipe with a flexible seal above to minimize fouling. This is the same mechanism I employ on my current surge actuators that have been in operation for three years. The only difference is that the entire fixture will be submerged now.
A good question is about failsafes... power goes out mid-surge and all surge valves are closed and overflow is down... now what?
I have that issue on my current system too and I solved it by having my Apex and all actuators on a UPS. If main power goes out, all actuators default to steady state mode and wait for power to return.
A good question is about failsafes... power goes out mid-surge and all surge valves are closed and overflow is down... now what?
I have that issue on my current system too and I solved it by having my Apex and all actuators on a UPS. If main power goes out, all actuators default to steady state mode and wait for power to return.
karimwassef
Active member
Great water displacement concept!
Someone used it for an intertidal tank
https://youtu.be/RuQR_jhtEfg
jccaclimber
Member
I would be more worried about the ATO not getting confused with the tides, that seems the greatest risk for a large drop in salinity or flood.
Do you want a two position overflow (this is fairly easy), or infinitely variable within a range?
Two position you just leave a flexible pipe out and put an air bladder underneath. Fill to raise to a stop, flood to lower to another stop. Leave the joint somewhat guided, and you're there.
Do be careful to avoid pinch points where a snail might become trapped and jam the mechanism at the same time.
Variable is a touch harder, although a lever through the back wall seems like a possible way to hide an actuator.
A 4 bar mechanism might be the best way to control it through height if a slide doesn't turn out well, but once more, watch the pinch points.
I doubt you're going to jam up with coraline within the region that is frequently moving. Stop it for a couple weeks and there might be an issue, but I see it moving more frequently than that.
I think a very flexible hose, ie a coil of corrugated hose (or silicone if you don't want corrugated) going from the moving overflow box to a bulkhead in the wall is by far the best option for your drain. Telescoping fittings aren't usually meant to change position without being loosened. Any sliding joint will have wear issues that hose bending through a small range of motion simply doesn't have.
The overflow box in the back of my 300 is adjustable height. I made it with 1" pvc with o-ring grooves added slip fit in to 1 1/4" pvc, then held with a plastic set screw (on the wet side of the o-rings). It moves decently when lubricated (mineral oil for installation), or when going over a nice layer of whatever grows in the dark portions of the tank (thinking diatoms), but it isn't free enough to move regularly. Also consider that if my seal fails and the power goes out my overflow is effectively half way down the tank. I used double seals specifically to reduce flood risk, but it would not be sufficient for a regularly moving joint.
Do you want a two position overflow (this is fairly easy), or infinitely variable within a range?
Two position you just leave a flexible pipe out and put an air bladder underneath. Fill to raise to a stop, flood to lower to another stop. Leave the joint somewhat guided, and you're there.
Do be careful to avoid pinch points where a snail might become trapped and jam the mechanism at the same time.
Variable is a touch harder, although a lever through the back wall seems like a possible way to hide an actuator.
A 4 bar mechanism might be the best way to control it through height if a slide doesn't turn out well, but once more, watch the pinch points.
I doubt you're going to jam up with coraline within the region that is frequently moving. Stop it for a couple weeks and there might be an issue, but I see it moving more frequently than that.
I think a very flexible hose, ie a coil of corrugated hose (or silicone if you don't want corrugated) going from the moving overflow box to a bulkhead in the wall is by far the best option for your drain. Telescoping fittings aren't usually meant to change position without being loosened. Any sliding joint will have wear issues that hose bending through a small range of motion simply doesn't have.
The overflow box in the back of my 300 is adjustable height. I made it with 1" pvc with o-ring grooves added slip fit in to 1 1/4" pvc, then held with a plastic set screw (on the wet side of the o-rings). It moves decently when lubricated (mineral oil for installation), or when going over a nice layer of whatever grows in the dark portions of the tank (thinking diatoms), but it isn't free enough to move regularly. Also consider that if my seal fails and the power goes out my overflow is effectively half way down the tank. I used double seals specifically to reduce flood risk, but it would not be sufficient for a regularly moving joint.
jccaclimber
Member
1) Size your external sump volumes such that you can still surge at low tide.
2) Logic is great, but you don't want to be in a position where an actuator or logic failure (other than maybe a runaway ATO which is harder to avoid) will take out your system (flood, heater stuck on, etc). Several years ago I was talking with a guy who was erecting a large steel tower for us (vertical acceleration sled for simulating helicopter crashes). He mentioned something and I asked "What safety equipment do you need for that?" His reply was "There are plenty of things we use, but the key to safety isn't relying on good equipment when you are in harms way, it is about not putting yourself in harms way in the first place".
karimwassef
Active member
Hmm.. I was looking for controlled actuation at several points so that I can simulate slow tides as well as fast surges.
I've solved the ATO issue with my current surge. I simply stop the surge for a period of time - I like to think my fish call it "finally - quiet time!" - and then take a sample to decide if it's ATO time.. if it is, run for a few minutes. You can calibrate it and it works without issue.
The air bladder is an interesting option.. hmmmmm... I don't trust bladders but I like the idea of air actuation underwater... maybe the entire bottom of the "platform" can be an inverted bathtub that is filled with water or air... to move down or up...
I'm not comfortable with flexible hose in a linear section though. A bend in the wrong place and the whole value of the drain can be compromised. I've used the extender joints for hours of ongoing and interrupted operations. They use triple o-rings and haven't failed on me yet... They only stick when they're not used for very long periods of time and even then, the force of a 200lb actuator is enough to move them. I've taken my surge actuator apart expecting massive damage each year and it's still in good shape. I'll find that thread here in a bit.
karimwassef
Active member
Agree. Better to not have to depend on equipment when being safe. Not sure how to completely eliminate risk other than having a secondary redundant power system and pump on a very simple mechanism. A true passive solution may not work... But even under worst case - all things failing - the water would be 3" down.. not an empty tank or anything.
