Micro Bubbles
Dear Crew,
<Steve>
I'm having problems with micro bubbles. I have a Panworld 40PX dedicated to a chiller and a sea swirl and I'm not having any problems. I also have a Gen-X Mak4 that is dedicated to 2 sea swirls and that is where I'm having my problems. I have siliconed all connections, placed a sponge in the sump and I'm still getting the micro bubbles. I notice at times that I will get a surge of bubbles that will shoot out both of the sea swirls, could it possibly be the pump?
<Yes... you may be able to detect a small air leak... with a length of tubing placed near the pump... and your ear... or a spray bottle of water spritzed about the volute... or simply turn all off, secure the intake, discharge lines, take the volute off, clean and re-lube the 0-ring... and put back together. DO check all flexible connectors on the discharge side up to where the lines enter the water...>
This is a new set up and I do not have any corals as of yet. Will this be a problem if the bubbles do not stop?
<Possibly... sometimes such problems "solve themselves" (mainly through gentle salt creep)...>
Any insight or suggestions would be greatly appreciated. Thanks Steve
<Maybe have another aquarist mystery solver come over and look your system over carefully... Good hunting. Bob Fenner>

Marine Aquarium Plumbing: Dumpbuckets and Sand Filter 1/30/05
Hi. I have spent a day looking over you great site and couldn't find a answer for my question. I am relatively new and plan to a 6' 2' 2' with a 4'1.5' 1.5' sump running off a overflow straight into a fluidized bed
<this is a mistake already... raw water with solids will burden your fluidized filter (clog over time) and moreover, you should skim raw water first to remove as many organics as possible before going downstream to bio-filters. This will reduce nitrates... and the burden overall on water quality>
...but my biggest problem that I can think of is that the return is going to be running through two dump buckets and there is going to be water fluctuation and wave's in the main tank so every time a wave goes past the overflow it's going to get a lot water at once and none after.
<another mistake my friend... not only will this be untidy (salt creep and low water/exposure), but it will wreak havoc with protein skimmer performance anywhere inline. Dump buckets are a novelty and simply do not scale down to hobbyist sized applications. They are really just practical on public aquarium sized displays>
Will the fluidized bed be able to handle it or will I need some sort of buffering device.  Thanks in advance. Glen
<look instead at my closed lop manifold suggestion... do a keyword search on our website (Google search tool on the home page) for an article called "goodbye powerheads". Best regards, Anthony>

Overflow noise problem and solution
Hello Crew,
<Michael>
This one is easy since it is more of a suggestion to post for your readers then a question for you all.   As we are all well aware, today's manufacturers grossly undersize the overflow drains in standard tanks given the flow rate sought for some of the reef tanks setup today.
<Yes>
  Trying to
watch the budget, I purchased a stock 210, 30 inch tall tank with the standard twin overflows containing two 1 inch drains and two 3/4 inch returns.  I figured that somehow I would overcome the noise and flow issue.  
Noise is of particular concern for us since the tank would be in our family room.  As typical, I installed the Durso style overflows which eliminated the waterfall, gurgling and sucking sounds.  However, I was running a fairly high GPH (approx 1200-1300 GPH), which needless to say was overworking the drains.  In lieu of the sucking sound, we had a fairly loud draining sound similar to that of bathwater running through the drain in your walls, which resonated through the water column and into the room.  I tried several methods to get rid of the sounds but to no avail. The only method to quiet down that sound was to throttle back on the pumps and significantly lower the GPH - Of course defeating the desire of maximizing raw water to the sump and skimmer.  It became clear to me that the only way to eliminate both sounds and to have a really quiet tank would be to force the drain tubes as well as the overflow boxes to fill with water. Artificially restricting drain lines is highly frowned upon (and rightfully so) since the slightest change in the flow rate in that line could cause the tank to spill over into the room in which the tank sits - not good especially if the wife or husband is looking over your shoulder.  So, I endeavored on a simple modification which I think will solve both the noise problem and the overspill potential.   Since most overflows come with two pre-drilled holes, I removed the 3/4 inch return line and used that as a primary drain hole (no Durso tube). Of course I had to re-route the returns over the back of the tank as opposed to through the overflow but that was a small price to pay for the quietness that I gained.  In the intended 1 inch drain line, I inserted a Durso standpipe.  I then artificially restricted the flow on the primary 3/4 inch drain line such that the drains lines filled to capacity with water and caused the water level to slowly back up into the overflow box.  Once the water in the overflow box reaches the standpipe top, the standpipe takes over as a drain line but only needs to handle a fraction of what it is capable of handling.  I assume the system at this point has a built in warning device in that if the primary drain ever gets clogged with something, that ever so unfriendly roar of rushing water will return.  
<Hopefully>
Perhaps there is a flaw in my design and I invite you to let me know if I have any unforeseen issues that may creep up, but I think it will work.  Let me know if you disagree.
Thanks for the great site.  You guys and gals do an excellent job and are an invaluable resource to those of us who are just starting out in this challenging and stimulating hobby.
Best regards
Michael
<Mmm, well, I still believe in gravity... and would ask that manufacturers "up-size" their drain and return line fitting sizes... and that aquarists contact these manufacturers and ask the same... they WILL do this on special request... OR that people otherwise have the holes re-drilled or enlarged... small diameter lines are too likely to clog, become occluded... Bob Fenner>

Re: Overflow noise problem and solution
Bob,
<Michael>
Thanks for the response. I just thought I would share that with your group as I see it is a fairly common problem/question.
<Is very common... and I thank you>
I agree that a perfect solution would be to have the larger holes pre-drilled, but for those of us (myself included) that did not heed that advice, I think there is hope. As set up the drain system still relies on gravity while at the same time increasing drain capacity of a standard tank (with two 1 inch drains and two 3/4 inch returns) by 175%. The tank is whisper quiet and I am fairly confident that even if both 3/4 drains become clogged 100%, the 1 inch drains will handle all of the flow based on the circulation set.
Regards,  Michael
<A good point... and I hope you're right.... if it were me, my system, I'd practice test... plugging one of the 3/4" lines... and maybe one each of both sizes... to see if water hits the floor. Bob Fenner> 

- Tank Modifications, Follow-up -
One more question here please. <Sure.> Instead of running the returns over the top of the tank, could I just cut holes for the returns while I'm at it on the back glass? Here is my plan: (2) 1" overflows, (2) 3/4 returns for those overflows, (1) 1" drain for closed loop, and (2) 3/4 returns for the closed loop. All will be cut above mid point of the tank. Is this too many holes for a 58 Gallon Oceanic tank with 3/8 inch glass? <It certainly sounds like a lot of holes... would get in touch with Oceanic and ask them. Their tanks are typically thicker than other brands so it's possible that you would be fine.> Would it be wiser to just go over the top with a manifold or other returns? <Well, honestly for the trouble you are going through, any reason why not a larger tank? Would be easier to realize some of your goals.>
Thanks again, you are all a great help.
<My pleasure. Cheers, J -- >
 

Plumbing idea Hello crew. Attached is a diagram of my thoughts of plumbing my reef tank. <A nice graphic> I was hoping that you could give me your insight as to weather <A homonym... you mean whether> you think it will work or not. Do you think I need ball valves at the end of each T? <No, nor the check valve illustrated> Attached to each T will be some sort of diffuser. <I would leave off with these... at least for right now... likely not needed/wanted... the trade off in volume versus pressure...> This will all be housed inside a hood with the lights. Also my overflow is rated at 1400gph I was thinking of returning 1200gph to the tank (125g) is this too much? <Is likely too much for a/the refugium... I would either sub-divide the sump in two, with the living part only receiving 3-4 volume changes per hour, or add another transit volume sump altogether. Bob Fenner> Thank You in advance for your reply, Jeff

Re: plumbing idea Hello again, Here is a revised diagram of my sump does it work? In the first diagram, will this create enough diverse water flow? Thanks Again, Jeff <Ahh, yes... I DO wish you were my editor/graphics supplier. Outstanding. Bob Fenner>

Reefuddled
Good evening Fine Fishy Folks!
<And a pleasant eve to you>
I have been all over the sump FAQ's and am now more confused than ever.  (TOO MUCH INFO! HA)
<Ahh, keep studying and ruminating then... all will become clear... as a driven snow on a cold October morn... wait, too much monstrous alliteration>
I am in the process of planning a 125 GAL Acrylic Marine tank and have some questions about overflows.
I am planning to put the 55 GAL sump in the basement and don't want to use Power Heads in the main tank.  Will be housing Fish, Clam, and some Soft Corals (hopefully).  What diameters should I use for the overflow and the returns?
<Please read here: http://www.wetwebmedia.com/plumbingmarart.htm
and, yep, all those Related FAQs files (above, in blue)>
Was thinking 2" Overflows (x2) and 1 1/2 " returns (x2)  Does this sound about right?
<Yep!>
Also, with approx 8' Head, any pump suggestions?  (Was leaning toward Dolphin pump/s)
<Good line. Again, there are quite a few files on Pump Selection... on WWM>
Thanks for all the great work you do.  You DEFINITELY make a difference!
Thank you,
Tom (the tool man).
<Man! I could've used your help yesterday replacing a water heater! Some knucklehead soldered on spin tight connectors! Argggh. Bob Fenner>

New venture into the saltwater world
I am getting ready to order my new acrylic tank.
<Ah, how exciting!>
I have done enough research to make me dangerous.  
<Keep studying until you are calm>
I have read in many forums and articles that the manufacturers of tanks are not drilling the holes big enough.  
<Yes, common>
This is what I have in mind for my new setup.  125g acrylic tank with a sump housing a refugium and protein skimmer.  I would also like to use the closed loop circulation system.  The tank will be used as a room divider with both short ends enclosed, but the long panels to be clear.
I will start out with fish, live rock and live sand.  If everything goes well I would like to add some coral in the future.  Would you please give me suggestions on how to have the overflow boxes placed and  also the number, location and diameter of the holes I should have drilled.
<Mmm, not so easily related... First off I (personally) would NOT use overflow boxes... You may see an overview of my ideas on marine plumbing here: http://www.wetwebmedia.com/plumbingmarart.htm
I STRONGLY encourage you to read ALL the Related FAQs (linked, in blue, at top), making a working drawing of plumbing, fittings, valves... and good notes re gear selection, installation and operation.>
I have found many diagrams of sumps and plumbing but not diagrams of the actual aquariums.  I can't wait to get ordering my tank and systems, but my uneasiness in this area is holding me back.  Thanks for any info you can give me,  Michelle.
<Best to take your time here my impetuous friend. Haste makes big waste at this stage in your development. Bob Fenner>

Re: Plumbing Question
Many thanks.  I guess I can use two Mag 24s instead coming out of the sump instead.  The Reef Central calculator shows 1400 gph for each using my set up,
<Uhh, beware of such "calculators", generalizations>
but I worry about the sound/impact of running 2800 GPH through the sump.
Am I just being nervous??
Dan P.
<Mmm, not "just" or it's at least both of us... Am sorry that this vehicle (writing, the Net) is not very satisfying (to me...). Have you read through the survey piece on WWM re marine plumbing? Please do: http://www.wetwebmedia.com/plumbingmarart.htm and the MANY Related FAQs files (linked, in blue, above)... taking good notes, making sketches of your possibilities... better to put in the time, effort in the design, planning stages here. Bob Fenner>

Overflow Boxes - Noise Reduction
Hello Crew,
<How goes it?  Maddox here, listening to 'Korn - Beating me Down' and thinking how fitting it is...because in the time it took me to answer this, several more emails came in... ;)>
Thanks for the great resource.  Only wish I had more knowledge so I could join forces to help answer questions for you.  Maybe someday as I am fairly new at this.  Quick question regarding overflow boxes which I could not locate an answer on the site.
<Thanks for letting us know it helped.  We can usually use help here...but you must have had a decent amount of aquatic experience.  I read the daily's once a week or so for ~6 years and had aquariums for 10yrs before volunteering...and most of the time I feel I know just a little above zero>
I have just set up a 210 gallon tank with twin overflows.  As most others, I am trying to deal with the noise factor by using pre-manufactured Durso style overflow tubes (All Glass Aquariums). <The standpipes, or regular tubes?> Even with the tubes, we are still getting a fair amount of gurgling noise, etc.  
<Is it mostly echoing out of the overflow box, or resonating from the tubes?>  
A friend of mine has a single overflow set-up which he modified as follows:  In lieu of the overflow tubes, he set a crate (lighting grid) at the bottom overflow box then filled the overflow boxes with bio-balls.  At the top he placed a thin sheet of poly filter to eliminate the cascading sound (which he replaces weekly).  The set up is remarkably quiet.  I was wondering if a similar set up for a reef tank would be ok or would that create a longer term biological problem.  I would not thinks so, but you all are much more suited to answer the questions than I am. My set-up will use an 80 gallon sump in the basement with a My Reef Creations MR3 Skimmer.
<If you were diligent about replacing the poly filter, it shouldn't be a problem in a 210.  You could also cut a cover out of acrylic, or even ghetto rig it with a folded towel draped over the top of the overflows :)>
Thanks for your time.
<Glad to be of service>   
Michael
<M. Maddox>  

Plumbing Question
I am planning a new 125 gallon tank and have a plumbing question that I cannot find the answer to in you comprehensive archive.  I want to achieve 20 times flow, so have special ordered a tank with two overflows with 1.5 inch drains and 1 inch returns.  I would like to use the Dolphin Ampmaster 3000 that has 1.5 inch fittings in and out.  Instead of running all of the flow through the sump, I was planning to have one drain go into the sump and the other connected by a tee fitting right at the pump intake, essentially making that overflow a closed loop.  After leaving the pump, I would tee off the 1.5 inch line and reduce the pipe size to 1 inch before returning to the tank.  Will this work or will I need a valve on the "closed" portion to ensure all of the lower head pressure sump water is returned at the same rate it drains?
<Mmm, let's see... you're planning on using the one pump to draw water from both the sump (that is gravity fed I take it) and one of the 1 1/2" overflow fittings? If I understand you here I would not do this... for a few "reasons"... principally the likelihood of a power outage, pump failure... that would drain the water down through the pump and overflow lines... and depending on the size of the transit volume sump, position of the through-puts, over on to your floor... I encourage you to draw all this out, including plumbing, fittings, valves (I would have these before and after the pump/s) to facilitate their manipulation/removal... and a large sump, possibly another as a refugium (low flow)... Whatever pump you end up with I would NOT reduce the discharge of the line size from the volute. In all likelihood you are looking at using two pumps... perhaps one can be used for the sump/s and protein skimmer... Bob Fenner>

Pump(s) for a Oceanic 200-gallon RR FOWLR Aquarium, actually overflows, pump/plumbing considerations
Hello,
<Hi there>
            Hope things are going well for you guys and gals. Please give me your recommendations for a pump to return water from my sump to a FOWLR aquarium. The Oceanic Rep. States the aquarium has a flow rate of 1400/2000 gph. The 2-return lines to the aquarium will be 3/4" PVC pipe and the drain lines will be 1" PVC with Durso Standpipes.
<Uhh... two 3/4" inside diameter lines? I think the estimate of how much flow you can realistically expect from these fittings is dangerously over-expectant... Hear me out please... I would NOT design, install or maintain a system that did not have at least fifty percent redundancy in provided capacity here... that is, for example, if one drain line would do, I'd have two of the same size... You do NOT here... depending on how you rig your plumbing, what sort of screening you have over these two drain lines, you can be in GIANT trouble in short order... should one become occluded. DO consider your options... if it were me, my system, I would have it (re)drilled for at least two 1 1/2" inside diameter overflows (2" holes)...>
Presently my options are to use 2-Iwaki MD30RLXT pumps (960 gph @4') with the outlet reduced from 1" to ¾" or to use 2-Supreme Mag-Drive 12 pumps (950 gph @ 6').
<Stop! Do NOT reduce the discharge diameters... and please show this correspondence to whoever has been encouraging you to do so... what you are suggesting is akin to buying an automobile with excess horsepower and driving with the parking brake on... don't reduce the diameter of the plumbing from your volute/s. Again, if necessary, have the available hole/s re-drilled>
The overflows are located on the corners of the aquarium. I am looking for pumps that are quiet, efficient, and dependable (who isn't, right). Should I use higher flow pumps and throttle-down the flow with gate valves or will that hurt the pumps.
<Might... will increase waste heat production, your electric bills>
I was also told I could add two more return lines to run along the back of the aquarium and use a larger pump. If you know of a better option, please suggest. The system will also have a refugium and Euro-reef Skimmer. This is the correct flow path, water to protein skimmer, to refugium, to pump, to aquarium or water to sump to protein skimmer, to refugium, to pump, to aquarium? Using a refugium will be new to me.
<Mmm, a bunch to say. First, please read through our archived FAQs on Pump Selection: http://www.wetwebmedia.com/pumpselmar.htm
and the linked files (above, in blue)... then the MANY FAQs on Sumps, Refugiums... you can find them indexed here: http://www.wetwebmedia.com/marine/setup/index.htm
You DON'T want to run this much, all the water through a refugium... maybe you can fit another sump for transit volume... Bob Fenner>
Thanks,
GDG

Re: Pump(s) and through-puts for a Oceanic 200-gallon RR FOWLR Aquarium
Hello Bob,
Thanks for the reply and I told the LFS to call Oceanic and hold my aquarium because I need the holes drilled larger.
<Ah, very good>
I have been reviewing the posts on the website and I thought I had it correct for the aquarium set-up. The flow set-up I was going to use was the one included in your "Plumbing Marine Aquariums" article on the site that has a picture of the refugium. I will have Oceanic install three overflow boxes in the aquarium, on both ends and one in the middle. The drain holes will be 2" drilled and the return holes drilled 1 3/4", thus having 3-1 1/2" PVC drains and 3-1" returns. I will redo my plans for the Euro-Reef skimmer CS (12-1), sump size is not determined as of yet, and 58-gallon refugium. Your comments are greatly appreciated. Could you recommend so books that could be of help with FOWLR, I have your book already? Thanks again.
GDG   
<Anthony Calfo's "Book of Coral Propagation" and our "Natural Marine Aquariums, Reef Invertebrates" books, though sounding like they are strictly "reef" would be of good use to you... mainly to further firm up what you already know intuitively, and will want to know soon. Sorry if this "plug" seems overly self-serving, but these indeed are your next best sources of input. They may be available at a local library. Bob Fenner>

Tank plumbing
Greetings Crew!
I am in the process of upgrading my 40 gal tank to a 75 gal (w00t, yes...) and have a couple of (nagging?) questions. I have read, read, and re-read countless articles you have on the WWM archives re drilling the new 75gal acrylic tank.  I have drilled the overflow (2" through put) (center overflow)
<I'd make at least one more.>
but am still undecided (hesitant?) to drill the returns.  The tank itself does not lend to the non-drilling (pump -> t-bar -> over tank output) type of return, so it must be drilled.  Currently I'm thinking of having my Iwaki WMD30RLXT (1" output) branch off to 3/4" t-bar to 4 returns (4 return holes in tank).  I know that 2 of them will be on the outside, and high up (re power outage/siphoning), but the other 2... I *was* thinking of placing them on the same plane and just have them pointed more downwards in the tank for circulation purposes.  Should I maybe consider another approach, what
would you do if this were your tank?
Thanks as always,
Craig
<Your approach is a good one... if you wanted to, you could drill just the two holes for two discharges each, tying two each together inside the tank... Bob Fenner>

- Tank Modifications -
Holy moley what a site!! You guy's really put a lot of effort into this stuff and I sure appreciate it. I have a 58 gal Oceanic tank that I am going to drill to mirror Mr. Calfo's design. If you could spare a couple of moments, I would like to get some clarification on a few specifics:
1) For the internal overflow, can I use acrylic or should it be made of glass? <Acrylic would be fine.> If acrylic, can I use Weld-on for adhesion to glass? <No... Weld-on will not bond the acrylic to the glass. You must you silicone adhesive... 100% pure, made for aquariums.>
2) Should "teeth" be routed into the acrylic/glass? <It would be best.> If so what do you believe is optimum spacing and depth? <I'd say at least one inch in depth... spacing is really up to you. What "optimum" is varies to much to say.>
3) I am planning on drilling 3, 1" ID (1.75 OD) holes for 1" bulkheads. Does the internal overflow have to span the entire length of the aquarium or is this merely suggested? <That would likely be excessive... probably better to use the shelf design proposed by Mr. Calfo.> If it is best to span the entire back of the tank, where do the returns come in if I wish to use Sea Swirls? <With Sea Swirls, you have no choice - they have to be positioned somewhere along the top of the tank... seems like you need to make some decisions - some part of your plan needs a drastic change.>
4) As for the bulkheads, I plan to cut them 2" down (center of hole) from the top frame and evenly spaced from the sides (not to come close to 2" from either side). Does this sound ok or is 4" to center better? <Sounds ok either way.>
Like all others before me, I appreciate the time you spend to answer these questions.
Mark
<Cheers, J -- >

- Tank Modifications, Follow-up -
Thanks for the prompt response. <My pleasure.> Just one point of clarification. <Sure.> I meant to say that I would be using the shelf design as outlined in the book. My concern was is it possible to drill the holes needed centered on the back wall, 2" down from the top and sufficient distance from one another, and have this shelf built to span only what was needed to cover those drains (I.E. 12" - 16" of shelf covering the drains along the back wall)? <Should work fine, yes.> Then I would have space at either side of the shelf for returns, be it Sea Swirls or whatever. What do you think? <Yup, makes sense and will allow for the Sea Swirls.> Lastly, how far down from the bottom of the bulkheads can I end the shelf? <Likely right below the bottom of the flange.> In other words, if my drains are cut at 2" - 4" at center and the bulkhead bottoms are at 3" - 5", can I end the shelf just below the bulks? <I think so, sure.> Will this hamper water volume/flow in any way? <It may, but the beauty of silicone is that you can remove, re-glue if necessary. You are going to do a full set of leak tests before you fill with saltwater, yes?>
Thanks so much for al of your help!! <Again, my pleasure.>
P.S. Do you know any tank drillers in Northern NJ? <I don't - you should check on some of the forums, I'm sure you'll find someone in your area capable of doing this.>
Thanks again!!
<Cheers, J -- >

Overflows
If it were your tank: How many & what size holes would you have drilled on the back wall of the tank (assuming a pump that can handle 3600gph at 6-8ft of head)?
<For a 180 gallon, likely six foot tank? Three, one toward each corner and one in the middle... of 1 1/2" inside diameter>
I have heard that the reason people do the in-tank overflow is that the water builds up after going over the overflow creating more of a vertical push into the outflow tubes vs. a couple top of the back tank holes which outflow horizontally.  Does that make a substantial difference for flow?
<Mmm, am concerned I may not be understanding you here, but the only real difference in such arrangements is the addition of horizontal piping, fittings, rather than more initial vertical drop>
If I understand you correctly, it sounds like your advice would be to drill 2-3 holes on the upper back tank walls, use bulkheads & screw in strainers, and then on the outside of the back tank wall, simply connect hard or soft plumbing leading to the sump?
<Yes>
What distance is advisable for the holes to be drilled from the top of the tank?
<Two or four inches in this case/size bulkheads... to either attach screening horizontally or (with the four inch gap) attach threaded elbows... Bob Fenner>

Building  a large glass tank
I am planning to build a 180 gallon glass aquarium. <Hey Mike, MacL here with you today.> I am new to the hobby and have tried to read as much as I can on water circulation/overflows. <Very smart.> I plan to do FOWLR, but would like to plan for the eventuality of going
reef.  There is a lot of articles discouraging the use of hang on overflows. <I think that's because many of the overflows have problems.> I have read a little on Durso overflows, horizontal overflows, some of the DIY overflow designs.  It has all become a little confusing. <I can see where that would be.>
In your experience/opinion, what are the best options for high flow, and as silent as possible overflows. <Personally I would drill the tank for optimum overflow and I'll be honest and tell you that my first tank originally was set up with a corner overflow and I will NEVER do that again.  I have ended up with a lot of detritus that I cannot get to clean it up in the overflow and I hate it. My newest tank will have the holes drilled into the main part of the tank and on the back. Let me know what you decide and if you have any more questions. MacL>

Central pump feeding skimmer 1/5/05
Hi. I purchased an AquaC EV 120 with your recommendation and it has been working great with the mag 5. I recently set up a 125 gallon reef and am still using the same skimmer but with a central pump for three sea swirls and the skimmer. Is it going to be possible to properly adjust the skimmer? The pump is overkill and is throttled back on all SeaSwirls and skimmer. It is an Ampmaster 4600 .I was told this would decrease heat (one pump no powerheads}
thanks. Manny  <Using on large external pump certainly will decrease heat.  As long as you have a separate valve to control the skimmer, you should not have any problems.  You may consider placing two valves in line to the skimmer.  The first one could be adjusted for proper flow and then never touched again (you could even remove the handle). The second would be used to turn the skimmer on and off for maintenance.  This way you would never "mess up" your adjustment.  Best Regards.  AdamC.>  

- Overflow and Water Level -
been searching at the FAQs but to no avail..
a quick question here..
how do I set my desired water level at my display tank?
I have two choices re-over flow;
1.) a hole drilled at the lower back side that can hold 2" PVC ending a stand pipe;
how tall should be the standing pipe in order to achieve at least 3" water line below the top edge?
2.) a 2" bulkhead drilled at the back; how far from the top edge it should be drilled to get water line same as no.1?
waiting for your help, again.. thanks!
-Arnold
<Hello Arnold.  When you install the stand pipe I would keep it a length about 1/2inch lower than where you want you actual water line. A lot is going to depend on the flow rate of the pump.  If the pump gph exceeds the ability of the standpipe to remove water then you will need to put flow control on the return.
James (Salty Dog)>

Re: overflow
my tank measured 22" in height but I'm keeping my water line down to 19" all the time (it's a freshwater tank and converting to salt) and I want to run it same way for the SW. and assuming that height would be fair enough for fluo lighting..
thanks J, happy new year!
>>>Arnold (",)
<Hello, by fair, did you mean "far enough away".  If you use a glass top it really doesn't matter where your water line is, and you should use a glass top to prevent premature rusting etc of the light fixture.
James>

- Overflow and Water Level -
Been searching at the FAQs but to no avail..
a quick question here..
how do I set my desired water level at my display tank?
I have two choices re-over flow;
1.) a hole drilled at the lower back side that can hold 2" PVC ending a stand pipe;
how tall should be the standing pipe in order to achieve at least 3" water line below the top edge? <How tall is the tank? With a setup of this type, the water level will be just a quarter inch or so above the top of the standpipe. So... you can trim the standpipe to adjust the water level.>
2.) a 2" bulkhead drilled at the back; how far from the top edge it should be drilled to get water line same as no.1? <Again, where you put the bulkhead will determine the water level... in this case you can bet that the water entering the bulkhead will be at least half its diameter, perhaps a little more.>
waiting for your help, again.. thanks!
-Arnold
<Cheers, J -- >

Bulkhead and flow rate...vs. gravity fed flow rate?
Hello,
Quick plumbing question here. I currently am running a successful reef 90g. I want to add a small ...40 gallons prop tank beside it.
<Neat, sounds good>
I intended on feeding it through a section of U-shaped pvc at 1/2" in diameter,
<Mmm, stop! Do make that larger diameter, at least one inch, and double them (use two), lest one fail due to... many possibilities!>
and have a small return pump in the prop tank to return water back to display. Can anybody help me to figure out the GPH of a 1/2" GRAVITY FED U tube....siphon started. As well would this be the same gph if a 1/2 bulkhead were placed here at the side wall of the aquarium? thanks in advance.
<Mmm, there are formulae for calculating probable water level differences (what I suspect you're really after), but I would not be concerned with these... Other issues (like screening, figuring how to prime lines (with slip caps no doubt), and taking care to make the "U tubes" deep enough (for water changes, evaporation...)... are more important. Bob Fenner>

Re: bulkhead and flow rate...vs. gravity fed flow rate?
ok, I think I am confused....If I started a siphon by just sucking on a 1/2 inch tube....the flow would probably be fast correct. In that a small pump, like a maxi jet at 200-300 gph might not be able to handle the return quickly enough....whereas if I used a bulkhead, it would be a slower rate....though if I put a t on the outside for air induction, wouldn't that too speed it up? For example I have an outside overflow box with a one inch drain that handles a mag 18 with a final rate of about 950-1000 gph due to head pressure. So I was thinking to get or make a u-tube,....hang it on the side of tank....suck on it into my 40 or 50 gallon PROP tank....and put a small pimp in there to return right back to display.
<Uhh... do not, DON'T try what I think you're proposing unless these tanks are at about the same level. Please read here: http://www.wetwebmedia.com/plumbingmarart.htm
and on to the MANY marine plumbing Related FAQs (linked, in blue, at top). Bob Fenner>
again , be so kind as to provide me with your educated thoughts. I am rather well versed,....but kind of stumped here-----

Plumbing an overflow for a 72 gal
Hi I recently replumbed my 72 gallon bow front tank. I used 3/4" pvc down the middle in the back to about 4" off the bottom and then ran a T to run to both sides along the back with about 3/16" holes drilled along it all around about 15 to 20 holes on each side.
Is this in a good place or should it be up higher in the tank.? << Well I'm not sure I follow the design.  If you have holes drilled up high in your tank, then why have a pipe run down into the tank?  The main idea is to take the surface water right off the top of the tank and overflow it into the sump. >> I am running a Little Giant pump at a about 450 g/ph. Do think the pump is enough? << No, I would at least double that flow. But hey, that is just me.  Give it a look and see if you think it is enough. >>
Thanks
<<  Blundell  >>
Rodney Reible

Finding Aquarium hardware/gadgets
Dear Sir or Madam: I am looking for a clamp or bracket that will secure a drain hose to my refugium sump.  The bracket must fit over the top of the glass tank and must have a ring or clamp that I can use to secure a 1" or 1-1/4" drain hose.  In most refugiums, this function is performed by a bulkhead that is secured by a horizontal plastic or glass cover over the tank.  Such a horizontal cover is impractical for most do-it-yourself downstream refugiums and I am looking for a simpler solution.  If you know where I can obtain such a bracket or clamp, I would appreciate it. Thanks very much. Regards, Paul.
< For any kind of bracket or gadget I always check out aquatic eco systems @ aquaticeco.com. This is a great site for DIY aquarists. Get their catalog.-Chuck>

Making a homemade overflow
Dear Adam,
<< Hey Narayan. >>
   My Eheim 2227 wet/dry failed today. A few days ago it was unable to pump water up against the head pressure and I had to restrict the inflow just so that the pump can keep up. Today it started to leak out of a seal.... Fortunately it was devoid of media and merely added to my water volume and flow -It did give me some surge type flow though!
  I'd like to replace it with a 20L refugium under the tank. << I hope you mean 20 gal, because 20L is pretty small. >> My plan is to have a small initial chamber to add a media bag with carbon and PolyFilter , followed by most of the tank that will be 4" DSB, macro algae, 'pods, all lit up 24hrs or reverse -not sure yet... any opinions? << I'd go reverse lighting.  Sounds good to me. >>
And a final chamber with the pump that will be sized for about 100gph flow. << That is very little flow.  I'd go around 800 gph. >> The display is a 72G with 4.5" DSB and 75-80lb live rock.
Currently my circulation is just (2) Seio 620 powerheads and a Remora pro with Mag3 pump. Total flow 1700 gph in a 72G - probably more like 1200 gph and 60G of water...
  My tank is not pre-drilled. I am torn between a CPR overflow with the Aqualifter pump or a home-made over flow that will have (4) 1" U-tubes, each one quite capable of handling the 100gph flow should the other 3 lose siphon. I'm not sure I want to rely on the Aqualifter not failing -after all, I just had a $175 Eheim filter fail me is a little over 14 months! Which one would you recommend? << If you can afford it, I'd go with the CPR overflow.  If you want to save some money there are lots of people out there making their own overflows. Before making one I'd get some friends to come look at it with you. >>
Thank You,
Narayan
<<  Blundell  >>

Flow Meter 12/16/04
Hi Bob,
<Anthony Calfo in his stead :)>
I'm setting up a new 175gal reef tank & I was hoping to get some advice from you on where I can get a flow meter for my chiller line.  
<many of the online mail order companies stock such parts if you ask... the specialty places in particular like MarineDepot.com or CustomAquatic.com, perhaps... else you can try aquaculture suppliers like Area Inc. in (Homestead?) Florida... do an Internet Yellow pages search for these folks. I am sure they stock this item>
I've seen this mentioned on the site in various places but I'm not sure which type to get (or where to get it).  I don't want to put something in that will pollute the water in some way.  
<seek all plastic... avoid all brass parts which are FW safe but not SW safe>
I have a 3/4" flexible hose connection off a feed from my main pump. Thx very much Mike
<kindly, Anthony>

Balancing siphon, pumping flow rates
Hello,
<Hi there Luis>
I am hoping you can guide me. I have a 75 gln  reef set-up. But the aquarium I have does not have the overflow system or hard plumbing . So,  I decided to add a refugium tank under my main tank it's 24" wide x 8.25" x 14.25", I think it's a ten or 15 gallon... I went ahead and installed everything but I can't control the flow rate...The way I set everything up was with a siphon system..
<!>
The water is siphoned on one end with a 3/4 in pvc pipe and flexible tubing , it flows through the U.V sterilizer then it flows into the refugium, then bio balls and into the reservoir ..then it gets pumped back up into the main tank with a 600 gph submersible water pump...I even installed a valve to try and control the volume of water on both ends.
<There is no way to control this arrangement>
The problem is I can't get the water flow even, if the rate is to fast on one end the refugium dries out and if it's to slow it  over flows. A friend of mine suggested that I install a pump on the siphoning end so the out take can be the same as the intake; is this something that would work?
<No>
if so what about if there is a power failure?
<The water will drain to the level of the line, pump above>
I have to be also concerned on the set up in the event there is a power failure with flooding as I live on a 3rd floor. So I have to make sure in the event something like this were to happen it would not over flow.
any advise would greatly be appreciated.
Thank you,
Luis
<Basically you have two choices... drill/have the tank drilled or use overflow box/es. Bob Fenner>

Overflow holes on glass tank plus closed loop
Hi crew!
<Peter>
Great website! I love that you guys cover everything from the most basic to advanced stuff! But of course, I'm writing with more than just compliments :-)  
I had a few ideas I'd appreciate any input on. I'm having a 115 tall glass tank made (48" x 18"deep X 30" tall).
<Bet you'll soon wish this was eighteen inches tall, 30 deep>
Since it's being custom made (Starphire front panel) I'd like to take advantage and have the back drilled (like in Anthony's Coral Prop book) instead of an unsightly clear internal overflow box. Before getting into the hole size/type questions, I guess I need to ask about flow rate. I love the idea of a closed loop/external pump system (have one currently on my 20gal). If I get virtually all my flow in the tank from a closed loop system (up to 30X tank volume), how much flow do I actually need to have going through my overflow/sump?
<What do you want to do with this flow? 2-3 volumes per hour will do for a refugium for instance>
Is it dependent on protein skimmer pump/size (i.e. volume processed by skimmer vs. volume flowing through sump)?
<Yes... if that's what you want to service... let's say rather than a hang-on>
Or just enough so the heater in the sump gets enough flow? Any thoughts?
<Lots. For heating you don't need much flow either... water is the standard for specific heat... retains thermal energy better than any other substance known>
So then, if all I need is minimal flow going through the overflow holes in the back, would 4 - 1" bulkheads be sufficient on this size tank (haven't bought the return pump yet for this reason)?
<Fewer, larger would be better... like two 1 1/2" toward the upper, back corners...>
I noticed in searching through previous questions that 4 - 1" bulkheads (holes drilled 4 inches from the top of the tank to the middle of the hole) were mentioned as sufficient for a 120G tank. What GPH would I want to be going through these, assuming I want them skimming mostly surface water, and to keep them from being too loud?
<More to be considered, specified... like where, how does the water transit from there? How much higher will the water be over the edge/lip of these through-puts? Will there be any plumbing running horizontal from them? Practically speaking the two 1 1/2" fittings will allow much more than the 4 one inchers... a good six hundred gph... if you want more, think you might later... have them drilled for 2" inside diameter bulkheads>
Also, how necessary is it to have a shelf/baffle running across the entire back top of the tank to skim the water?
<No>
I'm thinking 4 - 1" bulkheads with minimal flow will be sucking mostly surface water anyways, right?
<You don't want this to happen... too much noise, too great a likelihood of something getting trapped there, too hard to rig intake screens>
Thanks for any input!
Peter
<Read over the archived "Plumbing FAQs" (there are many) on www.WetWebMedia.com until you are centered on your options here. Bob Fenner>

Re: Overflow holes on glass tank plus closed loop
Hello Mr. Fenner,
<Peter>
Thank you for the reply. Only after reading your response do I see how vague my questions were. So let me be more specific. Yes, I would rather have a deep tank instead of tall, but apartment constraints dictate size. So I figure rather than have large sump or refugium volumes, I'd put my extra volume on top, so to speak, therefore treating this tank like a 60 gallon with lots of swimming room on top :-)
<I see. I hope you have long arms!>
As for the plumbing...the plan is to have the tank drain surface water to a sump, where there will be a protein skimmer, heater, and media like carbon.
Dedicated pump will then return water to tank. Refugium will be separate, with a small dedicated pump from the sump; exiting water flowing back to the sump.
<Good arrangement>
If all circulation in the display is provided by a closed loop, then I can get away with how many gallons running through the sump?
<Depends on the size of the sump, fittings, plumbing... there are "average" minima (3,4X), and maxima (10,20X)...>
Let's say 600GPH is sufficient. Then, the drains from the main tank could be 2 - 1.5" ID holes in the upper back corners of the tank (how far from top/edge is safe for drilling/final water level)?
<Again, depends on the sump somewhat... Imagine a power outage, or outright failure... the water above the lip of the through-puts is going to drain down into the sump... need to test, mark the highest level the sump should be filled to prevent flooding... That being stated having the edge of the cut out down two inches and over four or so is about right>
I currently have a small tank plumbed like Anthony described in his book, with a simple horizontal line coming off the back of the near top of tank drain hole, then down to the sump. This is SO LOUD as air gets sucked in just under the upper lip of the bulkhead inside the tank.
Is this because there is too much flow running through a 3/4" hole?
<Only to a secondary extent>
Or because I should have put a T on the bulkhead on the back of the tank, with one part pointing up for air intake, and the other pointing straight down for the water?
<This would help... but what you really need is a larger diameter fitting/plumbing, all situated further down in the tank, a "Tee"/Durso fitting, AND a mechanism for silencing the water dropping (an aspiration tube)>
I think that if the hole was larger, the water would simply flow down, half filling the drain line, and not making the vortex of air effect it does now. Is this correct?
<Yes, possibly>
This is why 2 -1.5" ID holes would be OK for apprx. 600GPH? And a T on each drain coming off the back of the tank would not be necessary then?
<I would use this, yes>
These 2 drain holes would then determine the display water level, would they not?
<Mmm, only to an extent... the pumping mechanism is at least as important>
I did not understand why you asked in your reply how much above the holes the water level would be.
How could they be higher than the drain holes, unless the flow was too great (eek, overflow!), or the exiting drain lines curved up first?
<Bingo on both counts>
Thank you for any help you can afford me. A realize I could try things, and learn with trial and error (i.e. my super loud 20 gallon, doh!), but I'd prefer not to mess around with this new tank, especially glass. And I'd really like to avoid a large internal overflow box in an already "thin" aquarium.
Sincerely,
Peter
<Have you read over the materials stored on WWM re marine plumbing? You should. Bob Fenner>

Re: Overflow holes on glass tank plus closed loop
Thank you again for your reply.
<Welcome>
Yes, I have read through the archived WWM info, as well as tons of info on ReefCentral. I was just a bit unclear as to the size/placement of the drain holes on the display. But now you've answered my questions. Thanks again for you help.
Happy Holidays!
Peter
<Thank you Peter. To you and yours as well... am wondering, in ongoing wonderment re the issue of how one might impart (succinctly) what might need to be made known re this topic (marine plumbing)... As a person in the process of such investigation, do you have suggestions here? Would video work? Perhaps dividing, subdividing the print topic (with graphics) into sub-issues like "tank drilling", "cutting and solventing plastic pipe and fittings"...? Do feel I know (from study, practical experience, much trouble over the years) the basics of the topic, but perhaps not well-enough to relate to others. Bob Fenner>

New Reef Tank Setup, attention Mike B.
Thank you for your quick response.  In talking with my local fish guy I think I've decided on using 2 one inch drains in the overflow.  This would dump into the sump and then be returned by a mag 12 to two returns on the upper back
wall of the tank.  Both returns would be loc-line "Y" returns thus having water returned by spouts aimed in four different directions.  I am trying to avoid powerheads at all costs.  The only concern is when using the "Y" return and I aim one side low and one side high and the power went out would the lower half of the "Y" continue to back siphon after the water drops below the higher return on the "Y"?  Any feedback on this set up would be appreciated.
<Hello, I don't think it will be a problem as long as one of the spouts in the "Y" is high enough to suck air when the power goes out.  I would of course double check the set up by shutting the power off yourself.  If it doesn't work you can always drill a small hole in the "Y" before the split at the water level.  Or, a check valve can do the job.  Good Luck.  MikeB.>

Overflow questions
I am in the process of setting up a new 40g tank. I am obviously a newbie, and am worried about the possibility of my tank (or a sump if I go that route) overflowing. I would like to keep the tank as clutter free as possible. that is why I'm leaning towards getting a sump. My tank is undrilled so I would have to get an overflow which I heard are usually pretty reliable from what I hear, but seems like it could be the weak link.
<Yes... if it somehow fails, where will the water go?>
I was toying with maybe trying to have a good powerhead to feed the sump and a little stronger pump for the return (because it has gravity to compete with) with a valve on the way up to control the flow to try to sync the flow to that of the powerhead, or have the powerhead feed a protein skimmer the flow to the sump.  I have been told that this would most likely lead to an overflow, but I am new and naive so I wanted to get some more opinions on it.
<There is no way to adjust these two pumping mechanisms to achieve what you have in mind... float switches et al. are even less reliable than the overflow box>
Also while I'm bothering you I was also wondering if you need to be able to get the sump out of the stand.  I ask because the stands door has a small opening but on the top its larger so I could fit a larger sump in the top before filling the tank.
thanks
<Might indeed have to drain all to move away from the wall... Bob Fenner who suggests the use of two overflow boxes if one getting blocked, losing prime worries you too much.>

Bubbles in the tank
Hey guys, Hope you can help me; I've searched the FAQ and can't seem to find my situation.  I have a 75 gal, 120 lbs live rock, Top Fathom t100, sump with no bio material, one maroon clown - 0, 0, 0 readings .  Since set-up (one month) I have had many small bubbles in my tank, just thought it was normal since my local fish store has some running through their display tank.  Then I read your FAQs and became concerned.  I noticed that my clown does have many bubbles on him/her and they don't immediately go away after turning off the filtration system.  I removed the protein skimmer and they remained, then I placed filtration material in the sump input and they remained, I finally checked all of my PVC joints and found nothing, but . . . while my filtration system was turned off I fed my clown and notice him "burping" bubbles out of his mouth. <<  Bubbles don't concern me.... but this does seem odd. >> Soon thereafter this bubbles on his/her body disappeared.  I guess my question here is whether or not I have a serious fish health issue here or am I being overcautious in my tank management.  << Well for this, I think I would be cautious and curious. >>  Assuming I do have a real problem my thoughts are to follow-up my PVC joint-check with a pump rebuild.  Thanks for your input I'm inspired by your knowledge of aqua science. << Well the bubbles are coming from somewhere.  Turning things off one at a time may help locate the source, but fixing it will be another challenge.  Good luck. >>  Brad
<<  Blundell  >>

- Plumbing and Setup for a 120 -
Dear WWM Crew,
Many questions if I may to help reassure me before I have my tank drilled. I have read the books by Mr. Fenner and Mr. Calfo and have read through all of the plumbing FAQs on your website. I have also searched water flow questions from other reef sites, aquarium tank dealers and plumbing supply companies.
I plan to have a 120 gallon (4X2X2) glass tank with LR and 3 inches of fine sand. I plan to keep for soft corals (and perhaps hard corals in the future), feather dusters, a few "cleaner" shrimp, snails, crabs and a few compatible fish.
The tank will have two internal overflows, each with a 1 ½ inch drain pipe and a 1 inch return pipe. I estimate the total flow from the two drain pipes to be between 1350 to 2700 gph. [This estimate is derived from an estimated flow of 300 - 600 gph for a one inch pipe multiplied by a factor of 2.25 for the larger 1/1/2 inch pipe]. Based on your website FAQ responses and the Fenner & Calfo books I am hoping to avoid power heads, wave makers etc. <Do keep in mind that unless you deploy a distribution manifold [as described by Anthony Calfo] you will end up with a laminar flow in your tank, albeit a robust one. You may want to consider some SeaSwirls or similar device to make sure the return is well distributed around the tank, and not just in one or two places.>
Below the tank will be a 30 gallon sump (estimated to be 2/3 full) that will have a skimmer section (Aqua C EV 180), a refugium section and a return pump section. The sections will be separated by under-over baffles. The refugium will be for fine sand and rock. The water from the tank will flow directly into the skimmer section (from bulkheads drilled in the bottom of the tank), then to the refugium and then to the pump.  I have attached a diagram of the sump plumbing plan as a jpg file.
Here are my questions:
1) Is this water flow adequate? Or should I:
a. Have three overflow boxes each with 1 ½ inch drains. I am concerned that this will take up a lot of space in the tank. <It will take up space, and because I didn't see any specific mention of pumps... I'm not sure what you mean by "adequate". You've planned well by having 1.5" holes drilled for the overflows, but your circulation will also be limited by the pumps you choose.>
b. Have two overflows with 2 inch drain pipes. I am concerned that I may have trouble finding a large enough overflow box to fit such a large "Durso style" drain pipe that I would build. <Think you will be fine with the two 1.5" drains.>
2) Concerning a sump this size/description:
a. Can it handle this much flow (perhaps up to 2700 gph) ? <It can handle it, but probably won't be much of a refugium with that much water flowing through it. You might reconsider just using this as a sump and adding a refugium elsewhere.>     
b. Will the water movement in the sump be too turbulent? <You may find this is the case.> If so would a 40 gallon or 50 gallon sump be able to handle this flow? <It's not a matter of "handling" - it's a matter of what the movement of so much water will do... any sump will allow this much water to pass through. You may find you have other complications.>
c. Even with the baffles I am concerned about micro-bubbles. <Yes, and with the flow rates you are considering, this may be a problem.>
d. Will this much flow through the sump be disruptive to the refugium I plan? <Yes.>
e. Would a larger skimmer be better (EV 240)? <It wouldn't hurt, but will take up more room.>
3) Concerning the return pump
a. Is it better to have the pump outside the sump or is inside OK? <I prefer outside... submersible pumps tend to add heat to the water that may not be desirable. Also less of a mess to swap out, replace.>
b. If I buy a pump capable of handling this much theoretical flow, ~ 2,700 gph at the appropriate calculated head, and it appears the drain flow guess was too high and the pump too powerful, can the flow from the pump be adequately and safely reduced with a gate valve in line after the pump? <Yes.>
Thank you in advance. I have learned a lot form your website. I look forward to the next book on Reef Invertebrates. <Uhh... Reef Invertebrates has been available for almost a year now... perhaps you mean Reef Fishes?>
Chris
<Cheers, J -- >

Air bubbles and fish spots...
Hello crew!
I just want to say thank you for all the time and support that you and your crew provide to these questions.  
I've been looking online for the answers to these questions, but I can't find the answers to my specific questions.  
First, I have fine air bubbles returning to my tank clouding the water.  I know, don't say it; I have spent days reading the past FAQ's.  My particular problem is that periodically (every 20 minutes or so), a surge of bubbles enters the tank.  It's like the air is building up in the pump, then it spits it out.
<Yikes, not good... can be dangerous to your livestock... there is an intake leak... somewhere... that you should look, listen for and fix... a spray bottle of water, a length of tubing... for spritzing on lines, fittings, the pump volute... and the tubing for listening for intake "hiss"...>
I have siliconed all my joints before and after the pump and still microbubbles.  I don't have bubbles entering the sump so it is not coming from there.  I'm really out of ideas as where this air is coming from and how to solve the problem.
<With someone helping, try pressurizing the line (blocking the discharge/s...) you may see water seep to shoot out of the intake source... otherwise try wicking a napkin/paper towel along the entire intake line... for water>
  I have a 150 gallon with 100 sump below.  
Second question is not a problem, I'm just curious if you have seen this before and what it is...
At night, I often use the flashlight to see all the different life forms emerging.  I have six green Chromis and when I shine the flashlight on them, they have large 1/8 inch spots on the fish.  During the day, they have no spots and they are healthy.  Disease free for months.  Have you observed this before?  Normal?  Should I be concerned?  
Thanks for your input in advance.   Dan
<Likely what you observe, describe well here are "nocturnal markings"... changes in the fish themselves that may aid them in the wild in avoiding piscivorous predators. No worries. Bob Fenner>

Leaking plumbing questions
WetWebMedia Crew
I was wondering is this was received by you guys or not last Friday?
<< Not sure, but I'll do my best to answer this now. >>
I have an update to the below, I decided to switch overflow boxes anyway and have bought 2 Amiracle hang on overflows (not the 1 piece type, I had that already).  I wanted to put them in but the o rings don't seem to stop weeping water (from the bottom).  I don't know if they are too loose or too tight, it seems no combination will make it stop weeping when water is added to the operating height.  They are new O rings too!
I know from reading that I'm not to use any Vaseline on these, but should I use 100% Silicone aquarium sealant?  If so where? << I would, on both sides of the seal.  Also, I'd use Teflon tape or pvc glue as well. >> Does pipe thread tape help?  Any ideas? << Yes, a good way to go. >>
By the way, I'll have to get new glass cut, but they all ended up just fitting on that same side, so I don't have to re-route the overflow or return pipes to the other side (left) of the tank. << Great. >>
Thanks in advance!
<<  Blundell  >>

Return to sump limiting flow
Hello,
My 58 gal Oceanic reef-ready tank has a 1" return to the trickle filter (bioballs removed) that enters through a 90 degree elbow on top of the filter.  From the tank cut-out to the entrance on top of the trickle filter is smooth continuous ~18" vertical and 30" horizontal.  I am unable to get anything more than ~600 gph of flow without the return to the trickle filter limiting any further increase in flow rate.  Is there a better arrangement for the return to the trickle filter (e.g. a direct vertical drop into the filter, no diffusing tray within the filter, etc.)?  Thanks.
-Mike
<The horizontal run is the only thing you can easily change here to improve the situation... the shorter this is the better... But the diameter of the through-hull (the 1" return) is THE rate limiting factor. You really need either more and/or larger drain ports to assure more flow per time. Bob Fenner>

Intake too low
Hello, wishing good health and thanking you for taking the time to consider my question.
I have an uncommon setup.  I have  35 gal FOWLR. I wanted to add a sump but realized drilling
the tank wasn't possible once filled and later found out my tank is made of annealed glass so forget it!
<Can be cut... but not easy>
What I did instead is placed a pump in the display which feeds a 45 gal plastic drum. The drum has a bulkhead  
plumbed into it which gravity drains the water back into the display.  I felt this is a much better option then using
a crap over flow box.
<Mmmm>
The downside is that you must have the plastic drum slightly higher than the tank in order for the overflow to work.
And also the water level in the tank is not stable, as water evaporates or water changes etc, the display acts as a sump.
<Yes. Well put>
Anyways, my question pertains to a skimmer I am adding next week. I am getting an euro-reef and will place it at the correct height in the 45 gal drum.
My problem is this.  Experts say that in order to have a skimmer work properly, The water feeding it must come from the top 1 inch of the display. Problem is that the pump feeding my drum has it's intake near the bottom of the tank. And bringing it up to the 1"  level from the surface is not an option for various reasons.
Is this such a factor that it could prevent my skimmer from not producing any foam or should I go for it anyways?????
<I would go for it anyway... the difference in efficiency is minimal. Bob Fenner>

- Overflow Noise, Follow-up -
Hi again and thanks for replying, what I did was get a 3 feet PVC tube and this helped the noise now I am going to buy an elbow so the water doesn't go straight down will this reduce even more the noise? <To some degree, sure.> And another question when refilling the sump should I always use antichlorine, even when I left the water sitting or using water from 5 gal drinking water they sell. <You only need to use dechlorinator when you are working with tap water. Purified water will likely not have any chlorine in it.> and if I put water to sit does it have to have a powerhead in it. <It should.>
thanks a lot
<Cheers, J -- >

Help, too much info... Plumbing design 
Hey Guys!
<Slugster>
Here's my issue:  I bought a 125 and want to make it a reef  tank.  I have an overflow box that handles about 1400 GPH and want to  run a sump, skimmer, and refugium.  I was reading about head height  and was trying to figure out how my plumbing would be with a MAG 9.  If I  am planning to run the sump, skimmer, and refugium with maybe about 10  feet of head height (not including any 90* turns, if any) would a single  MAG 9 be enough?
<For the circulation to, from your sump/refugium, yes... though you will likely want to add more circulation... perhaps with submersible pump/s, powerhead/s, a closed look manifold...>
I really don't understand
this plumbing thing and need  all the help possible.  What should I do?
<Keep studying, talking with shops, other hobbyists, join a club, look at other set-ups... till you have a good enough idea of what your choices are>
Buy 1 MAG 9 and see what  happens?...wait?  I really don't know.  Please help me understand.  Can I run the system like this: overflow box with 1" pipes  into the sump -->skimmer --> refugium --> then back into the  tank?
<Yes, but I would up-size the plumbing from the tank to the refugium (to 1 1/2" inside diameter) and run the skimmer in a part of the sump, only have part of the water go through the actual refugium... maybe add another sump...>
Would the 950
GPH be strong enough to do all that? Or should I get a  second or possibly a MAG
12 to do it all?  Thanks for all the help!   
Mike in Orlando
<Keep studying Mike... no need to rush... haste makes waste... and wet floors. Bob Fenner>
*the --> stands for  water flow*

- Overflow Noise -
Hello,
I just had installed a 155 gal all glass aquarium with two overflow boxes, one in each side. The tank is in my room and the noise from the water falling into the overflow boxes is driving me crazy. The tubes going from the bottom part of the overflow to the sump are one 1' and another an 1' and a half in each overflow. I don't have the canopy done yet nor the metal structure covered with wood will this help for the noise? <Only slightly... what is making the most noise is the sound of water falling the distance of the overflow, followed by the sound of air being drawn down the drain of the overflow. Both can be addressed with a stand pipe, which can be built in a number of configurations.> What can I do to reduce the noise form the overflow boxes? <Do look further into WetWebMedia as well as around the net for a "Durso Stand Pipe" - a good design that will help reduce, though not eliminate the sound from your overflows.>
Thank you
<Cheers, J -- >

Marine Fish Only Plumbing
Good evening. Love the site. I visit every day and never fail to learn something new (and I've been doing this for 25 years!)
<Me too... and for even longer!>
I currently have 4 tanks, 3 salt & 1 fresh. I love fish, so these are fish only tanks (I am gathering info from your site and various books to give a reef tank a go early next year). In the meantime, I plan on upgrading my 125 (72" x 18" x 20") to a 170 (72" x 18" x 30"). By doing this, I can use the same stand (I checked with the manufacturer, it can handle the added weight) and canopy (I will increase the light output by adding a reflector, which it currently does not have.) I am NOT going to add any additional fish to the tank, just give the current residents (mostly angels, butterflies & tangs) some additional swimming room. (How quickly they grow!)
<Yes>
Most of my questions were answered by your terrific site, but there were a few that were not. My current tank has a 6" x 6" overflow in the corner. I was thinking about ordering the 170 with 2 overflows, one on each side. One would go to my current wet/dry. The other would go to a new sump to house a bigger protein skimmer (my current skimmer is in the wet/dry sump - from what I have read, this is not the best place for the skimmer.)
<Actually... there is none better IMO>
Yes - I am currently using bio-balls in the wet/dry, but plan to change this sometime next year. Anyway, my thinking is that by using two overflows to feed a wet/dry and a sump, I am 1) doubling the water circulation in the tank and 2) allowing the skimmer to skim water that has not just gone through the wet/dry. Does this make sense?
<Yes>
Or would it be better to pump the water from the sump over to the wet/dry? This makes sense, except that it would not increase the circulation.
<Better to go with the "A" plan... two separate sumps>
My final questions involve nitrates. As my fish have grown, I am doing water changes more frequently to keep the nitrates low. I currently do 25% every three weeks. I know that setting up a refugium (which I will do next year) and eliminating the bio-balls will help.
<Yes... you are spot-on>
My tank is currently decorated with coral skeletons and some rock (not live). Is it a mistake to remove the bio-balls if the tank has NO live rock?
<Mmm, no... not if it is, has been up in operation for a goodly time... and/or you are moving the established substrate, decor into the new system>
In the meantime, do nitrate reducers work? (I am talking about the chamber style that house "Deniballs" that supposedly turn nitrates "safely" into nitrogen gas.) Thanks for your help.
<They can... some are far over-rated... most are a pain in the keester to monitor, maintain... better to go with a DSB in one of the sumps, or better a refugium... a good stepping-stone to your trying a reef>
By the way - after reading the FAQs on protein skimmers for small tanks, I purchased an AquaC Remora for my 46. THANKS! What a great protein skimmer! Reasonably priced, very quiet, small, and IT WORKS!
(Something my SeaClone never did!)
<Outstanding. Thank you for your input. Bob Fenner>

Adding a screen to an overflow
I've searched your site and can't seem to find anyone previously faced with this situation
I have an in wall 150g Perfecto 48"x24"x30" tank- viewable from 2 long sides.
AMiracle XL Mudd Sump in basement (approx 35g?)
AMiracle 1400 gph? 1pc Overflow w/ 2 outlets (CPR style), plumbed with 2x Lee's 1" ID vinyl hose to basement sump (came with the XL Mudd filter).  With modified Durso standpipes for external overflow.
1" ID vinyl return from sump using Gorman Rupp 14-520 pump (16' head) to a 1" Sea Swirl
My problem is I just started with a beautiful 2-3" Sailfin tang that was doing fine acclimating into the new tank (which has cycled and been up for months).  The next morning he was nowhere to be found.  We searched the LR etc, but he ended up being stuck halfway through my modified
Durso pipes on the hang on overflow. << Some screening needed. >> Thank heavens the tank didn't
overflow (at least there are 2 overflow pipes).  
I took my water sample back to the LFS and had them test my water; they said all parameters were perfect; it wasn't the water that killed the fish.
I think the problem is he just got sucked into the overflow when he got too close.  According to my calculations
(http://www.championlighting.com/Products/Pumps/gri.pdf
) I am getting about 2000 gph which should be decent for my setup.  I tried cutting some egg crate and devising a physical barrier for future fish/snails etc but this slowed the water down and raised the water level dangerously high in the tank. << I like the egg crate idea.  If that is affecting your water level then you don't have a large enough exit hole or drain pipe. >>
My other option is to cut the vinyl tubing and insert a tee off the return with a gate valve and dump it back into the sump or hook it up to the protein skimmer so that I can take that pump out of the sump (heat). << Not a bad idea, but I like to increase my circulation as much as I can.  If you do this, then consider adding a closed loop or internal powerheads to the tank. >>
I'd rather not do this because I want a reef tank and could use the flow. << Agreed. >>
Another option is to try to squeeze in another overflow box although this would be a pain.  I would have to get new glass cut for the canopy and since this is an in wall tank and I don't have any more space on the right side of the tank (occupied by current overflow and sea swirl), I would need to route the overflow or return tubing to the other side of the tank, drilling through the cabinet the tank sits on since it's anin wall tank. << Yes difficult. >>
Is there another answer to all this?  Is there anything wrong with mydiagnosis? << Sounds good, but I'd check to make sure there isn't air in the overflow set up.  I have a hard time believing that it isn't able to keep up with that flow. >>
Thanks in advance, love the site!
<<  Blundell  >>

- What's Taking You So Long & Fish vs. Overflow -
WetWebMedia Crew
I was wondering is this was received by you guys or not last Friday?
<Hmm... very possible it got lost in the shuffle. Myself, I was out of town and not reliably on the Internet last Friday so... I'll do my best to answer your questions this time around. Apologies for the late reply.>
-- Previous Email
I've searched your site and can't seem to find anyone previously faced with this situation
I have an in wall 150g Perfecto 48"x24"x30" tank- viewable from 2 long sides.
AMiracle XL Mudd Sump in basement (approx 35g?)
AMiracle 1400 gph? 1pc Overflow w/ 2 outlets (CPR style), plumbed with 2x Lee's 1" ID vinyl hose to basement sump (came with the XL Mudd filter).  With modified Durso standpipes for external overflow.
1" ID vinyl return from sump using Gorman Rupp 14-520 pump (16' head) to a 1" Sea Swirl
My problem is I just started with a beautiful 2-3" Sailfin tang that was doing fine acclimating into the new tank (which has cycled and been up for months).  The next morning he was nowhere to be found.  We searched the LR etc, but he ended up being stuck halfway through my modified Durso pipes on the hang on overflow.  Thank heavens the tank didn't overflow (at least there are 2 overflow pipes). <Yes... very good to have redundancy when using hang-on overflows...>  
I took my water sample back to the LFS and had them test my water; they said all parameters were perfect; it wasn't the water that killed the fish. <A fish could have easily asphyxiated if stuck in the wrong part of an overflow. I am not familiar with this brand... does it not have a pre-filter/strainer? I would think most overflow strainers would keep out a 2-3" tang.>
I think the problem is he just got sucked into the overflow when he got too close.  According to my calculations (http://www.championlighting.com/Products/Pumps/gri.pdf) I am getting about 2000 gph which should be decent for my setup.  I tried cutting some egg crate and devising a physical barrier for future fish/snails etc but this slowed the water down and raised the water level dangerously high in the tank.  
My other option is to cut the vinyl tubing and insert a tee off the return with a gate valve and dump it back into the sump or hook it up to the protein skimmer so that I can take that pump out of the sump (heat). I'd rather not do this because I want a reef tank and could use the flow.
Another option is to try to squeeze in another overflow box although this would be a pain. I would have to get new glass cut for the canopy and since this is an in wall tank and I don't have any more space on the right side of the tank (occupied by current overflow and sea swirl), I would need to route the overflow or return tubing to the other side of the tank, drilling through the cabinet the tank sits on since it's an in-wall tank.  
Is there another answer to all this? <You might consider a different brand of overflow box which 'might' offer a different type of prefilter screen that could keep out errant tangs AND allow for the high rate of flow you want for your reef tank.> Is there anything wrong with my diagnosis? <Well... just keep in mind that often times situations that arise in our lives/tanks are of our own doing... we decided we wanted the high-flow system. You might want to consider a high-flow quarantine where you can get incoming fish used to the idea that the currents will be up... and of course there's also the chance this same fish may have been sucked into a powerhead so... there are many possibilities, things to consider.>
Thanks in advance, love the site!
--End Previous Email
I have an update, I decided to switch overflow boxes anyway and have bought 2 AMiracle hang on overflows (not the 1 piece type, I had that already).  I wanted to put them in but the o rings don't seem to stop weeping water (from the bottom).  I don't know if they are too loose or too tight, it seems no combination will make it stop weeping when water is added to the operating height.  They are new O rings too! I know from reading that I'm not to use any Vaseline on these, but should I use 100% Silicone aquarium sealant? <No, no petroleum products around the fish tank... did the overflows come with any silicone sealant?> If so where? <I'd hold off just yet...> Does pipe thread tape help? <Always.> Any ideas? <Well... I'm not personally familiar with this brand of overflow, so if it were me, I'd be talking to the people I bought it from and then to AMiracle before I talked to anyone one else for product support. They really should be helping you through a new setup.>
By the way, I'll have to get new glass cut, but they all ended up just fitting on that same side, so I don't have to re-route the overflow or return pipes to the other side (left) of the tank. <Oh... ok.>
Thanks in advance!
<Cheers, J -- >

Hole, bulkhead size
Hi I just got a 2inch hole drilled in my 135 gallon tank. what size of bulkhead would fit in here. I have a 1 1/2 inch but it doesn't fit. The base on that bulkhead in 2 1/2inches. Can you get a 1 1/2 inch bulkheads with a 2 inch base? hope this makes sense
Tristan
<Yes to the last statement. Look around... there are "thinner" outside diameter bulkheads (the ones for spas/Jacuzzis for instance) that have 1 1/2" inside diameter and less than 2" outside diameter. Spears makes these... and a few places (try MarineDepot.com) offer them for sale online. Bob Fenner>

Reef Aquarium Plumbing 11/9/04
Hi, I've been thinking about setting up my first reef aquarium and when I came to the plumbing I got a bit stuck.  I've been gathering info from other people's comments from your site.
<ah, good... I'm hoping you also saw the page on reef plumbing that Bob just penned last week>
I'm going to explain my aquarium's specs :
Capacity  : 100 gallons
I drilled five holes to accommodate 50mm bulkheads each across the width of the aquarium.  I'm planning to put a glass shelf in front of the holes to skim to water surface better.
<excellent>
I bought an Aqua Medic pump with a capacity 1700 gallons/hr.  
Now I would like to confirm for circulation purposes, whether one pump would be enough and I am also going to use the closed loop system.  Do you think the performance of the pump will decrease?
<they always do over time as they age and clog>
I intend to put coral and live rock and a few fish when I'm finally done with my setup.
<17X turnover is good... but if you pick SPS corals and some other demanding varieties, you may need even more flow.>
Also, regarding lighting, I've read that 2 x 175W metal halide should be enough.  Do you agree as the height of the aquarium that is the glass is 27 inches?
<yes... agreed... these lights are very fine my friend>
Thanks a lot for your help, Best Regards Charles Galea Malta
<very welcome my friend, Anthony Calfo>

Bulkhead sizes
Good morning WWM Crew.
<Good morrow to you Troy>
I am in the process of planning the filtration/circulation for a 120 gallon salt water tank and would like you opinions on bulkhead/pipe sizes.
<Okay>
The tank, as of now, is going to be FOWLR. What I was thinking was a 1" line going to a 29 gallon refugium, a 1" line going to a 16 gallon sump, and a 2" line feeding a closed loop manifold.
Could you please advise on this or what you think would be more appropriate along with pump sizes to push all this.
<Mmm, a few things... the drain lines need to be larger... at least 1 1/2" inside diameter... I'd make them 2"... and the discharge/manifold plumbing should be the diameter of the outgoing side of your pump volute, not larger>
Thank you very much for your time and knowledge.
Troy
<You'd likely benefit from reading the marine plumbing article and FAQs posted on WWM. Start here: http://www.wetwebmedia.com/plumbingmarart.htm
and on to the linked files (in blue, at top). Bob Fenner>

Blue return nozzles
Hi,
    I wanted to know if anyone handled blue return spray nozzles that match the blue bulk heads? If so who has them?
Thanks, Nels
<Mmm, don't think anyone makes these... you might try contacting the PVC makers like Spears and Dura... or a big pet-fish distributor of such parts like All Seas Marine (LA and Miami)... otherwise, perhaps painting your own will do the trick. Bob Fenner>

Drilled hole size and what to do with them.
Mr. Fenner,
                  First let me say how much I have enjoyed this site. I have learned a great deal but do get confused at times.
<I as well>
I am in the process of starting up a 150 Gal fish only tank, it has been 8 years since it was last running.
                 I read the entire plumbing section and got my tank drilled. I think it may be a bit too much though. I had 4 holes drilled that are 2 3/4 inch for the drains and one 1 3/4 hole for a loop return like you have described. The drains will empty into the basement 10 feet below. The sump is 55 gallon wet dry acrylic.
<Some through-puts now!>
                My questions are this........ Should I "cap" 2 of the bulkheads and just use two to return to the sump?
<I would, yes... unless you intend to have humongous flow through all four>
Should I use all 4 and connect two and two into a "Y" connection, or should I run all 4 to the sump?
<Could connect two of two together... but the cost of bulk-heads... I would likely run just two of the four together, and cap the other two>
BTW my wet dry has only two one inch holes drilled in the top. I will need to enlarge the holes to fit either 2 or 4 drain lines.
<Yes... or retro a drip tray, baffle of some sort to accommodate the flow from above>
                I am shooting for between 750-2000 GPH for flow rate. Did I overkill with the drains {4---- 2" pvc}?
<Mmm, yes, but better than under-killing it>
Hope this isn't too confusing. I am planning on plumbing to system next week and hope I didn't mess it up.
               Sincerely,
                                Jeff Resch
<No real problem to cut acrylic or glass and silicone over the other fittings. Bob Fenner>

Skimmer and plumbing questions
Hey guys,
WetWeb is great. Every time I get on the site, I learn something new!
<I as well>
Have you had any experience with Schuran skimmers? If so are they as good as Euroreef?
<Have only seen the former. Best to seek out multiple, actual-user inputs on BB's like reefs.org, ReefCentral...>
I am turning my wet/dry into a refugium. I would like to add two ten gallon sumps (1 for the return pump and 1 for the protein skimmer).
<Mmm, do look into larger volume receptacles, ten gallons is not much considering transit volumes>
On the one ten gallon sump, I am going to attach it to the refugium (wet/dry) by the 1 inch bulkhead. If I add the other 10 gallon sump it has to be elevated above my refugium do to space. This will also sit above the refugium "L" shape instead of a "T". This elevated portion will be where my overflow drains to and where my skimmer is located. My question is, how many and what size holes will I need to drill to make the elevated sump drain into my refugium?
<Depending on flow rate... about one 1 1/2" inside diameter in each>
Overflow 1 drain hose" ( runs great with my return pump Rio 3100)
2 ten gallon sumps 20" L x 12" H x 15 " W
wet/dry 24" L x 14" H x 12" w
Thanks so much,
Greg
<Bob Fenner>

Re: skimmer and plumbing question
Thanks for your quick response. Since I am no handyman, I have another question or two. My goal is to turn my entire wet/dry filter into a refugium. Is a ten gallon sump for my skimmer and a ten gallon sump for my return pump not big enough?
<Not likely, no>
Does this limit my gph circulation?
<Yes... when the pump/s is/are off... how much water will be in play? Drain to the lowest point... best to start off with the sumps filled as far as they go and turn on pumps... mark the sumps for the highest they should be filled...>
Unfortunately when I set my system up I never thought I would have to change any filtration around so my space is limited ( even though you advised to leave plenty of room in CMA). But what size sump for the pump and skimmer do you recommend?
<Need more info. re your gear, arrangement... but twice this should be about right... a twenty long>
Should set up baffles in the wet dry and add my pump to that and get a bigger sump for my skimmer sump?
Thanks,
Greg
<Yes and yes. Bob Fenner>

Re: skimmer and plumbing questions
Sorry to bother you again.
<Never a bother>
As I look at all the manufactured refugiums, they
rate a 24" L x 14" h x 12" w up to 150 gallons. This is the same size as my wet/dry.
<Mmmm, how to state this... it seems to me that often such sizing is "maximized"... No problem with having larger units... real troubles with these live sumps being under-sized.>
Should I just set up baffles in my current wet/dry. Or if I am able to find a 20 gallon container should I add it?
<Up to you... bigger is better... and sometimes there are advantages to having more than one container... ease of manipulation, isolation...>
Will a 20 gallon sump before my refugium help enough?
<Better than a ten, yes>
I am still waiting for Reef Invertebrates because not a single book store or pet store in Cincinnati carries it so I ordered it off the net. I was told that the stores were having a hard time getting it.
<Mmm... they're all welcome to contact me (in San Diego) or Anthony Calfo (in PA) as we are the source... and have this title in stock>
Thanks for your time and advice,
Greg
<Thank you... the NMARI book will very likely allow you to clear up what you want to do here. Bob Fenner>

Closed loop system
Hello,
I have a few questions regarding a 46g bowfront I'm in the process of setting up.  I don't have room for a sump, so I'm planning on using a hang on skimmer and an external pump set up in a closed loop system. << Good ideas. >>  I'm considering drilling the back of the tank for drain and return lines to minimize equipment going over the back. << Great idea. >> For the return, I thing I'm going to use two 3/4" lines coming from a SCWD.  My question is about the drain.
What would you recommend for the bulkhead size. << One and a half inch. >> I'm thinking that about 600gph(at 4 feet) should be about right for this size tank.  Any pump recommendations for this setup would be greatly appreciated as well. << More important is to make sure you use ball valves and unions, you will have to take the pump out for cleaning, so plan ahead. >> As
always, cost is a factor.  Thanks so much for the great site.
<<  Blundell  >>

- Bulkheads and Pumps -
Good morning WWM Crew.
I am in the process of planning the filtration/circulation for a 120 gallon salt water tank and would like you opinions on bulkhead/pipe sizes.
The tank, as of now, is going to be FOWLR. What I was thinking was a 1" line going to a 29 gallon refugium, a 1" line going to a 16 gallon sump, and a 2" line feeding a closed loop manifold.
Could you please advise on this or what you think would be more appropriate along with pump sizes to push all this. <As far as bulkhead sizes go, it all sounds do-able although two inches may be a bit excessive for a closed loop... at the very least make sure you have screens on the input and output sides so no one swims into it when the power is off. As for pumps... you're on your own there. There are many good brands and several sizes of each. Flow rates should be as high as is reasonable... if you could accomplish 10 to 20 times turnover for the system, you'd be doing well. Much more than that and you may be sloshing water out of the tank. However, I suggest you rethink the plumbing of the two one inch lines going to separate boxes... your overflow rate will be constant to both - if you put different sized pumps on each box, the one with the lower flow rate will eventually overflow. Much better, if you want a refugium to fill it directly from your main sump and let it gravity feed back into the main tank or sump.>
Thank you very much for your time and knowledge.
Troy
<Cheers, J -- >

AGA Dual Overflow
Hi,
  I am new to Lg. Saltwater setups so sorry if this sounds dumb. I ordered from a local store a 125 AGA with dual overflows that are rated at a max flow through of 600 gph per overflow. The store is telling me that I need a pump rated at 2400 gph for each overflow, is this correct? It sounds like over kill? That would mean if I used one pump it would have to be 4800 gph... wouldn't the tank fill faster than it could empty?
<Mmm, yes... even discounting for less than rated "performance", head, induced drag in the plumbing lines... I would NOT get/use a pump with more than 1,500 gph rating>
Sorry for a stupid question!
Kerrie
<Doesn't seem stupid to me... Bob Fenner, who has mopped, vacuumed up many, MANY gallons of water from floors>

About plumbing multiple sumps
Hi :-)
<Hello there>
I think I’ve spent tens of hours researching your wonderful site- perhaps too long because I still don’t have water in my tank!! Arrgg!! Lol  I appreciate all the ideas and help really.  You guys are wonderful.
<Well, thank you>
Oceanic 75g reef ready with one overflow(¾” and 1” bulkheads both for drains)
2 sumps( awesome 30 gal(28”x18”x15”deep) heavy duty non-bowing Rubbermaid
“strong boxes” rated for 500 lbs each! :-) Insert Tim Allen gorilla grunt here!)
<Hee hee! I remember seeing a David Horowitz consumer show years back in which they tried the Rubbermaid ad of running a "Brute" (tm) trash can through a compacting trash truck... sure enough, it popped back (repeatedly) into useful shape/condition>
Sump#1 (DSB, macro algae) Sump #2 (auto-top-off)
1” spa flex through wall down to sump #1 in separate fish room.
<Hopefully not too far a "run" (distance), as the one inch diameter line really does not conduct that much water...>
Connect sump#1 and #2???? With bulkheads and spa flex?
<Could do...>
1” bulkhead in sump #2 for return (little Giant with 1” outlet)
How do I connect these sumps?
<IF they are at about the same level (height-wise), they can/could be interconnected with a good sized (like 1 1/2 or 2" inside diameter) thru-hulls and a section of rigid or flexible PVC pipe...>
1)   At what height do you recommend I drill the hole(s) for the bulkhead(s) between sumps?
<Down at least four inches from the top... think about the issue of "transit volume" here... what amount of water will "seek its own level" if/when the pump/s are shut off? Can be calculated, but basically, the water from the upper/main tank is going to collect below in the event of power or pump failure... you don't want this water to overflow your sumps>
2)   What size and how many bulkheads? Do I need more than one in case of clogs?
<A good plan to have more than one, though not necessary in general in this application if the one is of over-size and screened>
3)   Do I need to connect elbows to bulkheads to keep everything underwater to keep from sucking air like annoying overflow noise?
<Not likely unless the pump/s are large flow-rate or the fitting/s too small or placed too high...>
4)   The water level in Sump #2 will always be lower than sump #1 ,right?
<Yes... unless the pump/s are off.>
Sump #2’s water level would drop if not for auto top-off?
<...Mmm, yes>
Also, my skimmer is part of a combo wet/dry unit(CPR-192) 7 gallons.  This will sit on top of sump#1 on shelf.  Is it OK to drop a small pump into sump #1 to feed the CPR and let the CPR gravity feed back down to sump #1?
<Yes>
This is temporary- I’m saving for the Aqua-C skimmer- does the Aqua C have a certain water level it needs- should I take this into account when drilling the bulkheads in sump#1??
<Yes and a good plan... to either build/make a shelf to support the skimmer or a baffle/panel to back up the water to about the right depth/height in a dedicated part/section of sump #1>
Thanks for any help you can give- maybe I’ll actually get water in there soon :-)
Sincerely, Jennifer
<No rush... you are wise beyond most aquarists in figuring all this out "on paper" before cutting, dedicating funds. Bob Fenner>

Plumbing issue
On a 150 gal. SW would the returns be better with 1" return split to four 1/2" returns or two 3/4" ( the pump is a 1500 gph) ?
Thanks, Nels
<The bigger the better. Leave all at one inch inside diameter if possible. Bob Fenner>

Re: Plumbing issue
1" split to 2 = 1" ?
<Yes... the size/diameter of the discharge on the pump volute... split with a tee to two one inch lines. Bob Fenner>

Plumbing issue
Would there be a difference in performance T to two 1" outlets compared to T to four 3/4 outlets?
Thanks, Nels
<Yes... what is the formula for surface area of a circle... pi R squared... Do the math. Which is greater... two one inch or four 3/4" openings? Bob Fenner>