New tank - overflow and other considerations

newkie

Premium Member
Hello,

I'm having a new tank custom built for me. I am thinking of a 50"x28"x28" (170gal). I am trying to design the overflow and need some help.

First, I plan on using an Ampmaster3000 (3000gph @ 4') return pump and plumb with 1.5" PVC to two or more outlets. This is secondary water flow, primary will be with Reeftec wavemakers and possibly Tunze Streams later. The questions is what diameter hole is required to accommodate the flow of this pump? Would a 2" bulkhead with a Durso or Stockman standpipe suffice? I would prefer not to scale back the pump, but will of course plumb it so it can be.

Second, I am considering a center overflow. Are there any considerations against a center overflow that I should be aware of?

Third, in trying to design the center overflow I have some options which affect the surface area of the overflow. I won't bore you with the details but I wanted to verify something. In your book you state that you want the "thinnest" amount of water to enter the overflow. From what I understand the bigger the surface area of the overflow the "thinner" the water becomes making it more efficient. Does this make sense? So a 12" x 5" overflow is better than a 5" x 9" overflow. A corralary is how much surface area is enough? Is there any number that for a given size tank you want the surface area of the overflow to be X?

Fourth, I believe I will have one large drain in the center of the tank which will hit a 45degree elbow and flow down the far right side of the cabinet and enter the sump. That compartment will also hold the skimmer. I've seen some designs where that chamber is filled very high with water before going to the other 2/3rds of the sump where the water is about 1/3 the height of the sump. Is this a way of reducing bubbles? Is there any way to calculate, based on that much flow and knowing the dimensions of the sump, how to place the bubble baffles? I am worried that if placed incorrectly that the velocity will be too high and the bubbles will be carried through the baffles. This also makes me wonder about having a large area with no baffles before the intakes. Any help here is appreciated as I am having my sump custom made so I have a lot of freedom... to mess up! :D

Fifth, maybe if the tank were longer I could really consider this but I have seen some people remotely locating their sandbed in the sump. I think my turnover rate would be too high to accomplish this. I don't even know if there is a way to determine how much surface area of a sufficiently deep DSB is necessary to accomplish denitification of a heavily stocked system to know if it would work.

Sixth, I plan on having a DSB in my tank and wanted extra height specifically for this (5" to be covered by the stand). I really liked the idea in your book about building a PVC structure to support the rockwork. The ladder structure to support a large overhang: what diameter PVC would you recommend.. would 1" be enough? 3/4"? I also liked the idea you had to expose openings and cover them with a screen to create a refugium inside the PVC. Because this structure has so much PVC burried in the sand I think I will take advantage of this to boost my pod population.


I have many more questions but figure this is enough for now. :D

Cheers,
Chris
 
--Cheers, Chris :) I'm not sure where to begin with your question. It really is a lot to answer in a simple e-mail, and much of it simply cannot be answered without knowing more about the livestock you keep, the husbandry/maintenance you intend, and if all such are compatibile. Its always a pleasure to share an opinion and I shall try to help here best I can. But, we really would need to chat in person or you need to chat with local aquarium design professionals/society members to get a good consensus on the physical aspects of your system. Its always better of course to see local aquariums and plumbing in action.

I'm having a new tank custom built for me. I am thinking of a 50"x28"x28" (170gal). I am trying to design the overflow and need some help.

First, I plan on using an Ampmaster3000 (3000gph @ 4') return pump and plumb with 1.5" PVC to two or more outlets. This is secondary water flow, primary will be with Reeftec wavemakers and possibly Tunze Streams later. The questions is what diameter hole is required to accommodate the flow of this pump? Would a 2" bulkhead with a Durso or Stockman standpipe suffice? I would prefer not to scale back the pump, but will of course plumb it so it can be.


---FWIW, I would not use the ampmaster... I have a strong preference for Iwaki for longevity and reliability. I also have a disinclination for some brands based on customer feedback from another website that I mentor on.

As far as the hole sizes and flow rates... I have no idea. Its not something any/many of us commit to memory. I would simply find a dealer/brand of bulkheads from where you intend to make your purchase and read the max and min flow ratings. Personally, I use Rainbow Lifeguard for convenience and contact them when in doubt. If you enjoy the physics of aquaristics enough to want to study these dynamics further, please do consider P. Escobal's book Aquatic Systems Engineering. Very fine book. A wealth of information.


Second, I am considering a center overflow. Are there any considerations against a center overflow that I should be aware of?


--- Some personal preference here. I don't like the sight and noise, or need to counter the noise, from them. I prefer overflows drilled on the back wall with a horizonatal overflow box. More discreet, easier to hide (polyps grown on the face and up high) and quieter from go without needing modification.


Third, in trying to design the center overflow I have some options which affect the surface area of the overflow. I won't bore you with the details but I wanted to verify something. In your book you state that you want the "thinnest" amount of water to enter the overflow. From what I understand the bigger the surface area of the overflow the "thinner" the water becomes making it more efficient. Does this make sense?


--- You are correct, my friend.


So a 12" x 5" overflow is better than a 5" x 9" overflow. A corralary is how much surface area is enough? Is there any number that for a given size tank you want the surface area of the overflow to be X?


---none that I know of. Its just a matter of finesse. If you have a light bio-load in the tank... you may not notice the difference in the ability of the skimmer to perform better for 1X versus 2X. But a mature or high bio-load tank will benefit from the max (length of the back wall of the tank perhaps as many aquarists do).


Fourth, I believe I will have one large drain in the center of the tank which will hit a 45degree elbow and flow down the far right side of the cabinet and enter the sump.


--- sounds like it could be a bad idea. Impedes water flow, is noisy, etc. Avoid this if possible. Frankly... avoid the whole center tower if possible.


That compartment will also hold the skimmer. I've seen some designs where that chamber is filled very high with water before going to the other 2/3rds of the sump where the water is about 1/3 the height of the sump. Is this a way of reducing bubbles?


--- indeed, it is best to catch all raw water for the skimmer first... and this chamber will baffle many/most bubbles.



Is there any way to calculate, based on that much flow and knowing the dimensions of the sump, how to place the bubble baffles?


--- heehee... you need to relax on the desire for formulas and calculations IMO :D This is... or at least can be... a very organic hobby. God bless you if you enjoy the physics of it... but its not me, and I cannot help with it. No formula is needed.



I am worried that if placed incorrectly that the velocity will be too high and the bubbles will be carried through the baffles. This also makes me wonder about having a large area with no baffles before the intakes. Any help here is appreciated as I am having my sump custom made so I have a lot of freedom... to mess up!


---- we get bubbles for many reasons. Excess elbows or other impedence in the run of the drain (hence why a slow, mostly straight drop is preferred) do cause some bubbles. But these are large and easily diffused. Scary bubbles are the ones that are aspirated/pressurized from pinhole leaks in the outflow plumbing. All again are easily avoided or corrected, though.



Fifth, maybe if the tank were longer I could really consider this but I have seen some people remotely locating their sandbed in the sump.



--- yes, very fine and works well.



I think my turnover rate would be too high to accomplish this.



---- hmmm... you are missing the point here. Not all flow goes through it. A teed bleeder from the outflow runs a slow feed on a closed loop back into the sump.


I don't even know if there is a way to determine how much surface area of a sufficiently deep DSB is necessary to accomplish denitification of a heavily stocked system to know if it would work.



--- for NNR on a tank your size lightly stocked... a five gallon bucket filled nearly to the top and unlit could be helpful or even adequate.


Sixth, I plan on having a DSB in my tank and wanted extra height specifically for this (5" to be covered by the stand). I really liked the idea in your book about building a PVC structure to support the rockwork. The ladder structure to support a large overhang: what diameter PVC would you recommend.. would 1" be enough? 3/4"?


--- some experimentation and engineering here too... but 1" would almost be too cumbersome for some. Good planning and 3/4" would be fine.


I also liked the idea you had to expose openings and cover them with a screen to create a refugium inside the PVC. Because this structure has so much PVC burried in the sand I think I will take advantage of this to boost my pod population.
I have many more questions but figure this is enough for now.

----very cool. Sounds like this will be a well-planned and successful system! Please share pictures with us all when complete :)

Kind regards, Anthony
 
Anthony,

This is going to be a SPS only system, filtration only DSB/LR and skimmer, basically moving my current system (see website) over to a new tank.

Regarding the ampmaster I've had this for a year in the garage, so I may as well use it! I have heard about the seal problems, and have the new seals to install. I am very familiar with Iwaki (had two of them die on me this year) and for my purposes anything above a MD30RLT is too noisy.

Regarding the hole sizes, I have found out that a 2" bulkhead should be capable of roughtly 80gpm so that should work although it will require one huge mother of a durso standpipe! :D Do you have a preference regarding Sch40 vs Sch80 bulkheads?

Regarding the notched back (and shelf idea from the book) I want to have the tank right up against the wall and all plumbing straight down. A) this convinced my wife to allow me to get a tank of greater width which I think will be great for aquascaping and B) although avoiding all leaks is impossible if all plumbing is internal then a basin and drain can be installed to the bottom of the stand (yes, I am crazy enough to drill a drain through my living room floor :D).

Regarding the center overflow drain going to one side of the tank, I had envisioned originally the drain going straight down to the sump then going down a channel with baffled which would lead to the skimmer chamber:
sump2.gif


I'm very open to ideas regarding the overflow. Now that you understand why I don't want plumbing out the back do you recommend something else? (A) stick with above plan for sump instead of plumbing water to the far side; requiring a more interesting custom sump and maybe extra baffles for the skimmer chamber or (B) One large corner overflow instead at the same side of the sump. Hmm, maybe that would work best? Something like 14x6 but in the corner.. the same corner of the overhang which will be about 24" tall (tank height 28").

Regarding the remote DSB, I see now... I don't think this is possible for me as the tank is so short I will be cramped on cabinet room (I may have the chiller underneath or in a little hut outside the house already! Although I hope with a taller canopy (currently 4" tall) a chiller will be unncessary).

I am trying to think of something interesting to do with all that room in the sump. Even if I don't use the 28long"x24wide dimensions, there is still a lot of room in there for more than bubble baffles. Maybe a frag grow out area or slow-flow algae refugium? Hmm... what to do.. what do to...

Good to know about the 3/4" PVC for the overhang, I will have to get a bunch of pieces and start building!

PS: Most of us are dealing with the limitations of what commercial product we have. Its quite a large responsibility to have created your own limitations with a custom job because you missed some important point. This is where I'm coming from.. trying to create a dream system without all the annoying problems of my current tank so I really appreaciate the help!

Thanks for the great response! :thumbsup:

Cheers,
Chris
 
--Cheers, Chris :)

This is going to be a SPS only system, filtration only DSB/LR and skimmer, basically moving my current system (see website) over to a new tank.


--ahhh, very good. And a pleasure to see it specialized/focussed. You and the corals will succeed so much better for it!



Regarding the ampmaster I've had this for a year in the garage, so I may as well use it! I have heard about the seal problems, and have the new seals to install.


--Whew! You are on top of it. Excellent.



I am very familiar with Iwaki (had two of them die on me this year) and for my purposes anything above a MD30RLT is too noisy.



-- Interesting. I wonder if it is consistent with "legend" that the Japanese made Iwakis are made better (flawless in my books)? Patriotism aside... I have only even bought Japanese made Iwakis and have used them commercially and industrially for about 15 years. I constantly try other brands other brands (several new each year) looking for a cheaper solution :D



Regarding the hole sizes, I have found out that a 2" bulkhead should be capable of roughtly 80gpm so that should work although it will require one huge mother of a durso standpipe! Do you have a preference regarding Sch40 vs Sch80 bulkheads?


-- no preference at all for our/aquaristic applications



Regarding the notched back (and shelf idea from the book) I want to have the tank right up against the wall and all plumbing straight down. A) this convinced my wife to allow me to get a tank of greater width which I think will be great for aquascaping and


-- it will also get you a divorce if the tower sounds like a flushing toilet :p Ha!



B) although avoiding all leaks is impossible if all plumbing is internal then a basin and drain can be installed to the bottom of the stand (yes, I am crazy enough to drill a drain through my living room floor ).

Regarding the center overflow drain going to one side of the tank, I had envisioned originally the drain going straight down to the sump then going down a channel with baffled which would lead to the skimmer chamber:


I'm very open to ideas regarding the overflow.


-- at least consider using street elbows to make softer bends. And although expensive, flexible PCV would be even better if you/we need to plumb a scenic route



Now that you understand why I don't want plumbing out the back do you recommend something else?


--Its really a matter of personal preference at this point... dealing with tower issues versus coming off the wall another 3-4" for back drilled overflows. My perspective is that the few lost inches are no harder to hide cosmetically than the humongous light canopy likely to be had for your sps system. A 4" swath of crown moulding to match the stand and canopy trim seems minor to me. Still... I would concede if you really don't mind the spave an internal overflow tower takes up. I'm sure that Durso and like modifications can also render the sound a non-issue. Your call, my friend.


(A) stick with above plan for sump instead of plumbing water to the far side; requiring a more interesting custom sump and maybe extra baffles for the skimmer chamber or (B) One large corner overflow instead at the same side of the sump. Hmm, maybe that would work best?



-- yes, I would indeed be inclined towards the latter :)



Something like 14x6 but in the corner.. the same corner of the overhang which will be about 24" tall (tank height 28").

Regarding the remote DSB, I see now... I don't think this is possible for me as the tank is so short I will be cramped on cabinet room (I may have the chiller underneath or in a little hut outside the house already! Although I hope with a taller canopy (currently 4" tall) a chiller will be unncessary).



--No worries... you willingness (I'm glad too!) for a deep sand bed in the display will surely be enough NNR. You certainly can forego the downstream denitrifier.



Good to know about the 3/4" PVC for the overhang, I will have to get a bunch of pieces and start building!


Thats truly great fund. Experiment in the garage with unglued pieces and dry tuffa rock for perpective. Even if you don't use the dry drilled rock in the tank... it is quite a minor expense for the final result and confirmation of design! Best of luck, my friend. Anthony
 
Anthony Calfo said:
-- Interesting. I wonder if it is consistent with "legend" that the Japanese made Iwakis are made better (flawless in my books)? Patriotism aside... I have only even bought Japanese made Iwakis and have used them commercially and industrially for about 15 years. I constantly try other brands other brands (several new each year) looking for a cheaper solution :D
Yes, the demise of both Iwakis was disappointing. I too have heard the MD series is both quieter and better built. One suddenly began to sound as loud as a vacuum cleaner and the other simply died. I am now using Blueline 1100 pumps and am quite pleased. Take a look at my review: http://reefcentral.com/modules.php?s=&name=Reviews&rop=showcontent&id=3

at least consider using street elbows to make softer bends. And although expensive, flexible PCV would be even better if you/we need to plumb a scenic route
What are street elbows? Yes, I do plan on using flexible PVC whenever possible. Also, isn't there a special "T" which is better for maximizing flow?


Regarding the overhang/aquascaping, would have happen to have pictures or know where I could see some pics of people who have implemented this?

Thanks again!
 
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What are street elbows?

--common construction lingo for a style of soft45 or 90 (not hard angled)... improves drainage. Do see/ask at the local hardware store


Yes, I do plan on using flexible PVC whenever possible. Also, isn't there a special "T" which is better for maximizing flow?


--yep... same as above. It has a soft "wye" at the crook



Regarding the overhang/aquascaping, would have happen to have pictures or know where I could see some pics of people who have implemented this?


--I do, but it would take an archaelogical experiment to find them quick. My apologies, but I am struiggling just to keep up with my e-mail presently. After the activity of the new book release, I would be grateful for a reminder and will try to find for you then, my friend. A couple months if you have the time.

Best regards,

Anthony
 
Hopefully I will be set up with the new tank by then. I posted in the main forum, hopefully I will see some.

I have some sketches I could scan and post if I could interest you for criticism.

Last question for now, would you recommend gluing the PVC structure? It seems that I could mostly assemble it w/o glue (maybe not at the tension points where the base supports the weight of the overhang) for added flexibility for changes down the line.

PS: Is there a new book? Or are you talking about your Coral Propagation book? I just got it at christmas with a nice note from you as a gift. Funny and informative reading.
 
Last question for now, would you recommend gluing the PVC structure? It seems that I could mostly assemble it w/o glue (maybe not at the tension points where the base supports the weight of the overhang) for added flexibility for changes down the line.


-- For the sheer weight of the structure with or without rock drilled and stitched to it, I would likely glue all pieces, bud.



PS: Is there a new book?

--Yes, and thanks for the easy seguey :D Information here. Co-authored with my good friend Bob Fenner and very much in our narrative writing styles, but illustrated heavily for the less than hardcore aquarists ;) Its the first of three volumes (April delivery)... see here:


http://wetwebfotos.com/store/nma-ri.html


Or are you talking about your Coral Propagation book? I just got it at christmas with a nice note from you as a gift. Funny and informative reading.


--- thanks kindly, my friend. Best regards, Anthony
 
anthony, not that you really care but just fyi I had a little giant last 12 years (three year hiatus), good record if you ask me, how long do Iwakis last?
 
12 years is awesome for a Little Giant :) Good to hear

Anything over 5 years is impressive. Did you ever notice that they also sell a sacrificial anode in their product line? Do ask an honest sales rep what thats for :p

Some would call it a solution to planned obselescence :D

IMO/IME 10+ years for Japanese-made Iwakis is not surprising. I've seen several that were over 16 years old.

Don't get me wrong... this is ultimately not a complaint against LG or any so-called "lesser" pump. You get what you pay for... sort of. Most Americans want less expensive and are willing to take a shorter lifespan to get it.

Case in point... there are Italian and German aquarium product manufacturers that produce all stainless steel components?!?! UVs, pumps, reactors, filters... wow! They are beautiful and built to last. And they would never sell here in America :p

Heehee... kind regards to all :)
 
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