dave w

Truthfully, it seems a little daunting to me, but I'm willing to explore it. I'm looking at how to turn over 3,000 gallons up to 20x per hour with the least amount of energy. If a piston accomplishes this, I will go with it. Intuition tells me that air lifts and propellers are efficient, but maybe that is just my traditional mind talking that is a little afraid of unknown new ideas.

Here is a picture of some of the block in place and some new footers which will support buttresses. The butresses will effectively break the sump into seven areas of about 300 gallons each. I am still learning how to post photos, sorry if this pic is a little small. And I know, one of the new footers is crooked, that will be OK.

Rob, sorry to be late answering this post. This sounds like a fascinating idea, but it is just a little over my head. Can you either explain it in terms my simple mind can grasp or show it in a diagram? Only Rob has seen my sketchup design so far and others may not understand this explanation, but the 20' long leg of the tank has two refugiums just a few inches above the water line, fed by geyser pumps. If I use the geyser pump to lift water a little higher, the fuges could empty into a surge device which then dumps into the tank all at once. I think this is very workable because geyser pumps can lift water quite a distance. I'll post the sketchup of the tank when I can clean it up a little, its just that I'm a little embarrased at my crudeness.

You're probably right about random flow, I will work on this once I can effect high tank turnover with slow moving equipment. There are a lot of problems that can be handled with high rpm pumps, but they don't support "plankton soup". My attempts to use slow turning propellers probably begs the question "why is a plankton system important?", and I think I owe an explanation. I'm trying to use plankton and high plant biomass for high water quality because I think the many millions of plankton are our largest water purifier. At 25 plankton per drop and 90,000 drops per gallon, even a 55 gallon tank has 5 million plankters, making them the largest biomass of our tanks, just like the reef. I'm doing a plankton system because I will be basing my tank on more than corals -- the sponges, shellfish and other filter feeders of the reef which do best when consuming lots of plankton while producing millions of their own plankton babies. For example, 200 oysters from the Chesapeake at maturity will not only clean 10,000 gallons of water a day, they spawn up to a million larvae 3 or 4 times a year. That's an average of 2 million plankters a day in the 30 to 40 micron range that pygmy angelfish larvae like. Sponges shed lots of cilia into the water column which are an important coral food. Refugiums produce millions of copepods (even benthic copepods and other organisms produce planktonic larvae). So if most of our tank produce free floating larvae, and I move water at speed that don't harm them, the tank may teem with clouds of animals. Add in a constant drip of phytoplankton, and I hope to mimic the reef in a way that I haven't seen in other systems yet. I hope this is a wrinkle that will make me a better reefer. It is challenging because it means unplugging high flow water pumps and protein skimmers, both of which remove plankton as fast as our tanks produce them and both are extremely useful tools for water quality. It may not work.

Then I will look into this type of system. I am a little fearful of an acrylic cylinder moving inside an acrylic pipe, it seems to me that grains of sand will soon scar it up. But there are many ways to modify the plunger. My first impression is that it looks expensive, but I may be wrong. I tried looking into diaphragm pumps but was turned off by the cost of industrial sizes.

Jon and others, please give me your opinion. Is it more important to have a surge device or in-tank water flow? While the ideal answer would be "both", with a tank this large I have to be mindful of my utility bill. Lifting water requires more energy than simply circulating it. Let's suppose that filling a 50 gallon Carlson device at 2' of head in one minute requires 200 watts of pump power. That same 200 watts might drive a propeller at zero head to move 8,000 gph in the tank. I would like to do both, but I think the priority is to get 20x tank turnover on the fewest watts possible. I think using an air device to lift water into the surge device is a great idea, but I haven't figured out the mechanics. I'm not the best mechanical mind around. Do people agree? Is it likely that the gravity of the water weight falling from the surge device will pull a lot of tank water along with it, and the 200 watts of surge power may circulate the same volume as a 200 watt powerhead. If so, count me in.

Jon, I have looked into Carlsons in the past, but admit that I don't know a lot about them. They are a great way to create surge in a large tank. But how does the water pump up those several feet into the surge device? To keep a tank teeming with tens of millions of plankton, I can't fill the surge device by traditional means -- the 1720 rpm impeller pump which (in my opinion) kills 99% of plankton. If we can find a way to lift water several feet without using an impeller pump, we are in business.

Chad, that is a very cool video. It looks like it displaces about a quart of water. In my case I need to turn over 3,000 gallons of tank up to 20 times per hour, so I think this is not a direction that works for my application. If I'm going to move 60,000 gallons an hour at slow speeds, I need large diameter propellers that keeps the G forces of acceleration within the soft bodied plankters ability to survive, so I've chosen motors that only turn at 105 rpm. The typical powerhead or pump turns at 1720 rpm. Although the prop blades only turn at 105 rpm, their 8" size moves a tremendous volume of water at slower speeds. I think the same 60 watt motor in a powerhead or low rpm motor will move the same volume of water, but the slow motor has perhaps one thousandth the G force of a powerhead.

Davelin, I have given that a little thought, but still don't know exactly what to do. I was thinking of mounting one of the slow turning motors on one of those motorized light rails and moving it through the tank. As I hope you can see, the horseshoe shaped tank has two curves and I don't think these light rails are made for curves. So my options are to get a light rails for each of the three sides, or be happy with one 20' rail on the long leg of the tank to stir things up. Putting a stationary paddle like you suggest would also do the trick. I have thought about large air blowers and even own a few, but they are somewhat noisy and in the winter they will cool the water a lot. In the summer they should do well. To run the geyser pumps I am thinking of using large diaphragm air pumps. They will displace a lot of water if I can keep down the sound of air exiting the top of the geyser pump chamber. It could be noisy.

It is 3,000 gallons for the display tank and another 2,000 in the sump. I don't really count the sump because I may just use it for copepods and artemia. Circulating the tank through the sump requires a high rpm pump that damages the plankton upon which this system is based. With the refugiums just above water level the sump won't be needed for a fuge. The folks in Hawaii needed 2,000 gallons of copepod culture to raise each batch of pygmy angel larvae, and I'd like to try this. I tried raising pygmy angel larvae before (without copepods) but always failed. Now that the Hawaiians have shown the way, it sounds like a good use for the sump. I have thought of wave devices, but lean toward a tidal approach on this tank, because low rpm motors with large propellers can't lift water vertically. Perhaps half the pumps will circulate clockwise for 5.5 hours, then all the motors will "storm" the tank for half an hour, then the other half of the pumps will push counter-clockwise for 5.5 hours to simulate tidal change. If I can incorporate a wave device and get the water up to the device without the high rpm pumps, I would be interested in that. Would your idea of a motor/fin fit within these parameters? Can you explain how this would work?

Actually I asked my brother about that one and he said aquariums are outside of the building and inspection codes.

Here is a picture of the footings of the west half of the tank.

Here is a picture of the footing on the east half of the tank.

This pic was taken just before excavation. The door is in the master bath and used to lead out into a greenhouse that was destroyed by the heavy snows last winter. The bobcat is one of my favorite toys.

Larry, having spent much of my life in the construction trades, few things put me to sleep faster than construction details.

Humidity will be a large problem, especially in winter. At Justin Capps recommendation I will keep polycarbonate covers on the tank in winter to reduce humidity and slow heat loss. I will install an air-to-air heat exchanger to flush out humidity and recapture as much of the heat as possible. I was originally going to put this tank in my basement office, and my wife was constantly worried about humidity and leaks. I can't describe the look of relief on her face when I told her I would build the sunroom addition for the tank. I will circulate with low rpm pumps and geyser pumps to keep plankton alive, so the excellent Hayward pool pumps will not work here, although I'm pretty sure you were joking. I don't know what the Swimjet is.

I'll enlcose some sketchup drawings as soon as 1) I clean them up a little because I'm embarassed about my crude sketchup abilities and 2) I figure out how to post them along with the first pictures. Hopefully just a couple of days.

3000 gallons! Wow! Are you going to go with all natural lighting, heating, and cooling for the tank? Yes, Davelin315, I will go natural as much as possible. The polycarbonate glazing is supposed to let in about 92% of the sunlight, but I will need some kind of LED track light for evenings. The system is set into the ground to act as a natural heat sink in the winter and cool sink in the summer to moderate temperatures. I will plumb it with pex tubing for radiant heating. And the sump is around 2,000 gallons to help with temperature moderation. Very nice... where are you located? would like to see this sucker!!!! Rocko918, I am in Fairfax Station, about half an hour from you in Bristow. You are welcome to come by any time, especially if you are employed as a block layer! Wow, that is huge. I was planning to do the same thing so I will be watching this thread closely Coral Hind, I think the size of the tank is not necessarily related to the amount of work required if you keep your filtration and water moving systems simple. This tank will be plywood and fiberglass, so doubling the size may only take 10% more construction. I love how everyone's idea of what "large" is varies Chad, because only the front of the tank is acrylic and the filtrations systems are simple, I hope the maintenance will be more in line with a "small" tank. Putting pictures on here is simple- zygote2k, thanks for the guidance. I'm sure it will seem easy to me after the first couple of pics are posted, I'm just not familiar with the process yet. For that matter, I don't know if I am cutting and pasting correctly right now! I generally lurk on forums and don't post much. Most of my pics so far have been on my blackberry, I have yet to find my wife's nice digital camera to take pics. Wow that is huge! I will be following along...please share photos as you take them! DCreefer, thanks for the encouragement. Construction photos will probably bore most people, but I have been mulling over filtration systems for a while and the integration of these systems into the construction may pique the interest of some folks. Everyone, thanks for the interest so far. I won't make you wait very long before posting pictures and asking your advice.

Hey folks, I am building a tank in my sunroom addition, although it might be more accurate to say that I'm building a sunroom around the tank. To keep the heating and cooling bills to a minimum, the sunroom is buried into the earth about 5' and on the south side of the house. The tank is horseshoe shaped. The roof, south and west sides are glazed, the east will be a solid wall because trees block the morning sun, and the north side of the room is up against the house. I will start posting pictures whenever I figure out how. I have excavated and have poured footings, block should start this weekend, if it doesn't keep raining. I have kept large tanks for 25 years but have been out of the hobby for 8 years, so I have a lot to learn. I am amazed how far the hobby has progressed over the years. I look forward to the help and advice from the people on this forum.

Nice tank and beautiful angels. Maybe one evening you can catch their spawning behavior.

Now that I've moved past the design and have begun building my new tank, how do I go about starting a build thread? Many thanks.

I've never kept these particular angels, but their retreat to a cave at dusk doesn't sound like the typical pygmy mating behavior. More typical is the male chasing the female for the last 45 minutes before the lights go out, and then "soaring" up to the top of the water column together with a cloud of gametes released at the top. Then turn the lights on an hour later and all your shrimp are sitting at the water surface skimming fresh eggs into their bellies.

Hello folks, I'm new to WAMAS but not really new to saltwater. But I've been out of the hobby for a while and am quite surprised to see how far the state of the art has come along. Anyway I have a 600 gallon acrylic tank on which a vertical front joint (corner) has seperated about half an inch, also causing a crack along the bottom (horizontal) joint. Is there a local company that does acrylic repair? This piece looks to be about 1.25" thick. Thanks. I'd attach a pic but I'm out of town right now.