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FAQs about Overflows, Bulkheads/Through-puts, Stand-Pipes, Holes vs. Boxes... Sizing, Number, Placement 4

Related Articles: Overflow Box Arrangements, Plumbing Marine Systems by Bob Fenner, Myth of the One Inch Beast (Why Relying on One Inch Overflows... or Overflow! Is foolhardy) by Scott Vallembois, The Flowrates through various Bulkheads (In relation to overflow drains) by Scott Vallembois, Plumbing Return Manifolds, Refugiums,

Related FAQs: Through Puts Placement/Number/Size 1, Through-Puts 2, Through-Put Sizing/Number/Placement 3, Through-Put Sizing/Number/Placement 5, Through-Put Sizing/Number/Placement 6, & Overflows 1, Overflows 2, Overflows 3, Overflows 4, & FAQs on: Rationale/Use, Through-Hull Fittings, Hang-On Selection, Plumbing, Troubleshooting/Repair... Marine Plumbing 1, Marine Plumbing 2, Marine Plumbing 3, Marine Plumbing 4, Marine Plumbing 5, Marine Plumbing 6, Plumbing 7, Plumbing 8, Plumbing 9, Plumbing 10, Plumbing 11, Plumbing 12, Plumbing 13, Plumbing 14, Plumbing 15, Plumbing 16, Plumbing 17, Plumbing 18, Holes & Drilling, Durso Standpipes, Make Up Water Systems, Pumps, Plumbing, Circulation, Sumps, Refugiums, Marine Circulation 2, Gear Selection for Circulation, Pump Problems, Fish-Only Marine Set-ups, Fish-Only Marine Systems 2, FOWLR/Fish and Invertebrate Systems, Reef Systems, Coldwater Systems, Small Systems, Large Systems, Water Changes, Surge Devices,

Hole Size - Approximate - theoretical Maximum Flow 1/6/09 Hi All, <Hello Jose.> please understand that I have the utmost respect for you folks and for the labor of love this website must be. I honestly can't even imagine the amount of time and effort you folks put into keeping it running. I am most grateful that's to say the least! <Thank you.> My question is one that while I have lots of specifics about my situation, I will try to keep it general as to have it help the most amount of people and not simply my situation as I understand that is not the purpose of this site. I am wondering if there is a reference table or chart that depicts theoretical maximums for flow through a given hole size. Why I ask? <As a gravity feed? There is, not in print quite yet though.> Well I'm setting up my new tank and have gone through a bunch of the content on the site and while there is loads of info there (so far as I've searched I know I've only scratched the surface) it seems to be more case specific. I understand that there is no set in stone way to determine the actual amount of flow a given hole will have in a system as many things affect that other than the actual hole size (column height, density, temperature, reservoir water level, fittings, pipe material, etc) but if I could look at a chart and say 'okay a ¾ inch ID hole/pipe can possibly yield, under ideal situations a maximum of xxx gals per hour' that would be fantastic! . <I know, and it is coming soon!> I've read some stuff out there about calculating flow through a given orifice size and there are formulas out there but it requires lots of information about the specifics of the tanks. I came to realize that's its more experience of the types of flows achieved with a given hole size than anything else, so I figured I'd reach out for you guys. I'm desperately afraid to have a situation where my drains aren't big enough and on the other end I'm afraid to make my tank into Swiss cheese in fear of starving my pumps so before I go nuts I'd like to really know whether I'm good with the (3) ¾ inch holes I have or do I need to punch a few more through there. <Well a ¾' gravity fed line will only get you about 160 gph per. This is an actual tested, quantified value.> Now I'm a bit limited in what I can do as I could only get my hands on a 1 -- 3/8 inch bit(makes a ¾ hole). My tank is a 150G (48x24x30 ,I know its tall but I've always liked the taller deeper tanks rather than longer skinnier even with the lighting and flow challenges it adds)and I have a 45 gallon tank that will be a Sump/Fuge hopefully when this is all over. Total water volume with rocks and sand will probably be around 175 (maybe a bit less as I'm hoping to have a 5 inch crush coral/ag sand mix bed with about 150 pounds LR.) I was originally shooting for 1500GPH total flow through the sump but I don't think with the (3) ¾ inch holes I have I will get even close but I may be wrong. <Your suspicions are correct, not even close.> I've gathered from reading some posts that a ¾ inch hole would maybe get me 200-250 GPH so I'm guessing if nothing goes wrong and I have no clogs or anything I would maybe get around 800GPH out of the 3 holes I have, which I think is way too little but again I could be way off. <In reality a little more than half this.> I would greatly appreciate any help you folks could offer. Thanks all for you hard work and dedication to the hobby. You guys make it possible for allot of people to enjoy this most rewarding hobby. Thanks!!!! Jose Freyre <For this kind of flow you will need a minimum of two 1.5' throughputs, this will leave no redundancy. For my money the tank gets two 2' lines. Each one can nearly flow the entire 1500 gph. Welcome, Scott V.>

Re: Hole Size - Approximate - theoretical Maximum Flow 1/6/08 WOW-Thank you so much for the quick response! <Welcome.> Okay so I guess I'm drilling more holes huh...LOL. <Yes you will!> Would you say that's really the only option here? If it were you would you: 1)open more of the same holes(in different vertical locations as to create better surface flow because I'd be getting flow from different parts of the tanks surface area) <No, go larger.> 2)Widen the holes that already exist a) Bigger bit right over top of existing hole? <Can be done, an option.> b) Use a dremel and grind It out? (guy a lfs suggested that but didn't really sound like a good idea) <The Dremel can work, but it is a pain.> 3)Drill additional holes in the same vertical location just simply on a different horizontal plain (so stack the holes in the same column, I'm using a PVC pipe cut in half long ways to form a half moon channel from surface to base of tank and have water flow over the top edge into cavity it creates which will be filled with pebble and stones, near the bottom on the back glass pain is the bulkhead fitting)? <The way to go, drill yourself a larger hole or two within this overflow system.> 4)Just go with an overflow box to supplement ( I really hate this idea but would defer to your judgement)? <No, I strongly suggest drilling.> 5)Live with the low flow through the sump and augment with in tank power heads to move water around? <Don't do this either. Virtually any flow you run through these will leave zero redundancy, room for error.> Just thought of another option as well which is to use those holes (the 3/4 inch holes I already have) for returns and make 2new holes of the appropriate size between the 3 holes. <The route I myself would ultimately go depending on where the existing holes are placed. If they are too low you will have an overflowing sump when the return pump is shutoff due to siphoning and water draining back down.> I'm guessing (simply using additive properties which I'm sure is not accurate) that I would need something in the area of 2.5 inch holes, maybe 3 inch? Does that make sense? <Hmmm, a 3' hole for a 2' bulkhead.> The bit I used was from Lowes (lennox brand) and I have to say I think it stinks! All the u-tube videos I saw have people going through .5 inch glass in 20 minutes. It took my 1 hour + each hole!!! <Yeah, I have done this, it does stink. Do check out the diamond coated holesaws that have become so cheap over the last few years. My site does sell them: Glass-Holes.com.> Again thanks so much. Jose Freyre <Welcome, Scott V.>

Re: Hole Size - Approximate - theoretical Maximum Flow 1/7/08 Hello Scott!!! <Hey Jose!> Many many thanks for your help. Far be it from me to take valuable advice like your giving here and not follow it. <Heee, glad to help my friend.> I got my hands on some 2 inch bulkheads (3 to be exact). I was only able to get my hands on a 2 inch tube bit though. It all worked out in the end. I drilled right over top of the 1 3/8 inch holes and then used the edge of the drill bit )diamond encrusted) to grind it out the rest of the way. <Wow, gutsy and patient!> Put some silicone on the both the inside and outside flanges and that was all she wrote. I'm guessing I'll get something like 500-600 GPH out of each of those holes. So that puts me at about 1500-1800 GPH right? <Are we talking a 2' bulkhead as in 2' pipe? This would flow 1200gph plus per throughput. If you are talking 2' outer diameter on the bulkhead you are looking at a 1', perhaps 1 ¼' pipe, in which case the flow will be 300 gph and 500 gph safely, respectively.> At any rate I was able to get my hands on some really cheap (brand new from my LFS) Quite one Model 9000 Pumps( I know I know they aren't the best pump in the world but man I couldn't pass up the deal!!). They let them go for $99 each with full warranty and all. I couldn't pass it up. Originally I wanted to run 2 pumps so if one died I would still be at 50% but now with this new development (those pumps do 2300GPH at 0 head and about 2000 at 4 feet) I'm just going to run one with a gate valve after the pump and a t that dumps right back into the sump. If the gate valve is completely open then most of the water would flow right back into the sump. This way I don't burn out the pump prematurely and I don't blow my fish into the next county! <You can restrict the output with no issues.> For the returns I'm thinking using the same 2 inch drill bit and finding the biggest fitting it will receive (I'm thinking a 1.5 inch). <Mmm'¦even the smallest 1.5' bulkheads I know of need at least a 2 3/8' hole, the pipe alone is 2'!> I was thinking of drilling it on the side and running a 1.5 inch diameter pipe hugging the back wall of the tank (under the sand) and having it run from one end of the tank to the other (only slightly bumping out to clear the PVC overflows that will be siliconed to the back wall, I'm just using a 6 inch pipe cut in half)and capped off. Then every so often (as space permits) have a 3/4 inch pipe shoot straight up the back wall of the tank and run to the very top of the tank where it will be capped. All along the length I will drill a series of small holes in sets of 3 as to get roughly 180 Degrees of flow for each set of holes (imagine a pipe running north south and every inch or so up the pipe 3 holes in a straight line from left to right. The first being on the extreme right of the pipe just after the pipe curves around to face into the tank itself, the second one facing directly towards the front of the tank and the third facing the left. I would alternate the angle of the drilled hole itself in as random a pattern as I can manage. I'm thinking I will have at least 6 of these in the tank. I figure that will give me very good water movement in the tank. Combine with the 3 large overflows and what should be more than ample flow this should make for a pretty healthy tank (at least in terms of water flow) right? <It still sounds like your overflow drains are too small. As for the return, what you propose could work, albeit fairly complicated! Any open area in this system will need to be fairly high up, remember the caution of siphoning back into the sump when the return is off. Do checkout the following link. Combine this manifold with LocLine and you have an easy to build return that you can direct any direction. http://www.wetwebmedia.com/pbh2oret.htm> For lighting I got the 48 inch outer orbit with the 18 moon LEDs the 2 150W metal halides and the 4 t-5 actinics. I'm concerned about the overall depth of the tank so I hope those lights provide good light near the bottom (5-6 inch bed of sand/crushed coral) <Well with a 30' deep tank the 150s will be a bit weak towards the bottom. This is where placement of livestock comes into place. You can keep quite a bit under a 150, with the more lighting intensive corals in the upper 1/3, going down from there.> For the fuge/sump itself I have a 45 breeder that I will partition in 3 roughly equal sections. The right (looking at it from the front of the stand) will be the fuge. Then the middle compartment will be the return pump/s compartment. The left will be the "sump" where the skimmer and heater and whatever else will live (I will have a decent over under obstacle course to get the bubbles out on the skimmer side) The main drains from the tank will be plumbed individually rather than combined into one large pipe. My rationale for that is that I want to be able to see the condition and flow of each return. <Really a good practice.> This way I know which one is clogged or whatever. The idea would be 2 bring 2 of them into the 'Sump" side directly. The one left over would flow into the fuge BUT with a ball valve on it and a t flowing to the sump as well. This way I can control how much goes into the Fuge. I'm thinking I want to only have enough flow in there to get things moving but not enough to blow everything out into the display tank! This is also one area I'm confused about. Some people dig this idea and some people think I'm nuts for even thinking it. Could you offer some advice there? <Your implementation sounds reasonable to me.> Is it true that fuge's Don't like monstrous flows? <Within reason high flows will work.> Should I bother with the above setup to protect the fuge from my artificial hurricane!? Or is it okay to hammer it with all 1500GPH? <If it is stirring things up (it will) you do not want all of this to flow through the refugium.> Btw I forgot to mention that the half moon PVC up in the tank that will have the returns at the bottom of them will be filled with (from top to bottom) a sponge to catch particulates roughly one inch in depth, larger courser stones (about 1 foot worth) followed by small pea sized stones. The idea is I want to get the gas exchange on the course larger stones and the chemical filtering in the smaller stones Plus that will minimizes the clogging as well. So that's pretty much the setup (I'm sure I forgot things) but if you see anything you would do differently please please let me know. I'm eternally grateful for your help on this. Also before I forget I intend on having at least 150 LBS of live rock/some sort of stone_ in the display tank and some good LR in the fuge with either Caulerpa or red mangroves. Not sure if I want the additional up keep though for the mangroves as it's not as easy to keep I heard as just some Caulerpa. <The latter is where the real nutrient benefit comes into play.> I was also planning on doing a reverse photo period on the fuge lights. Thinking something like 12/12 with a 1 hour actinic overlap on either end for both the display and fuge just directly opposing times. <Sounds good.> Talk to you soon! Jose Freyre <You too! Scott V.>

Re: Hole Size - Approximate - theoretical Maximum Flow 1/17/09 Thanks so much for your response! <A pleasure to help out.> I'm relieved to here I haven't completely lost it. I'm also happy to hear that I don't think I'll need to drill another hole! Im heading out to Lowes now to go ahead and grab the new fittings I need . I will go ahead and go with the 1.5 inch for the main branching into 3/8 inch with 1/16 inch holes. <Better to start small, can always be enlarged!> As far as my livestock that is an awesome question. I honestly have to slap myself for not including that earlier so sorry about that. My plan is to cycle with 6-8 B/G Chromis for a couple months and eventually having a variety of hard and soft corals and reef safe fish. <Do be sure to research each addition re compatibility with each other and your system!> I currently have a couple of anemones (green BTA aka "Casper"- smaller size about 5 inches across, and a sebae aka "Sheila" - larger in my opinion about 10-11 inches in diameter but I heard they can get huge!- sorry about the naming it's just my wife has this uncontrollable impulse to name everything in the tank. I swear I'm the only person in the world with names pieces of live rock and snails.. we actually have names for all of our cleaning crew!) which I will move over with Bob my Oce Clown. <Mixing anemones with corals and particularly each other is trouble. See: http://www.wetwebmedia.com/anemcompfaqs.htm.> I'm thinking I need LOTs of flow for the corals but a more diffused but forceful flow. Not a directed JET type of flow that a nozzle would afford. That's why my mind was stuck on the spray bar idea. I'm thinking that would give me a more even diffused flow while still getting large volumes of nutrient/oxygen rich water passed all my filter feeders/inverts which is those' little guys lifeblood. Again I'll take this whichever way you want me to as I'm by far on the newbie scale . <For what it is worth I do only use the nozzle type outputs. Spray bars can work, but are a pain to setup (as you now know!) and can require more maintenance as far as cleaning/unplugging.> The one thing I'd like to stay away from is power heads. I'm definitely a "power head hater" lol. Well Hopefully I'll have some pics of the finished plumbing this weekend and I will post. Looking forward to everyone's feedback. <Sure thing Joey. Have fun setting up, Scott V.>

Re: Hole Size - Approximate - theoretical Maximum Flow 1/18/09 I'm filling the tank!!! I cant believe it!!!. Finally!!. I tell you if I never walk into a Lowes again for the rest of my life it will be to soon!!! <I hear you, congrats!> So quick tid bit of information I just learned. I was pleasantly surprised (actually quite pleasantly) to find that when I unpacked the Outer Orbit fixture I purchased from a gentleman on craigslist as a "48" roughly 560W fixture (2 x 150 MH-HQI, 4X 54W T5, 18 Lunar lights) is actually 48" 729W Fixture (2 x 250 MH-HQI, 4 x 54 T5, 18 Lunar) !! I cant even believe it!! But anyway the question that pops into my head now is. You mentioned early on that given my tank dimension (48W X 24D x 30H, taller than normal) the pair of 150's would be borderline insufficient. I was looking up the possibilities of a 250 upgrade when I took a closer look at the unit and noticed that the info I assumed was wrong and that this unit is the higher wattage one. Given this new bit of info, how do you think I stand in the lighting department? Feed back? <Looking good, 250s are the way to go here.> Concerns? Should I put stuff closer to the bottom , step the light intensity so nothing gets burned? <You will want to be sure to acclimate anything you put in the tank to the lighting depending on the lighting on their previous system. See: http://www.wetwebmedia.com/acclimcoralslight.htm.> Just want to make sure I don't bake anything and that I get the most out of this most fortunate twist of fate. As always thanks for sharing your knowledge and advice. It makes the experience some much o Joey Freyre <Happy to help, have fun. Scott V.>

Re: Hole Size - Approximate - theoretical Maximum Flow 1/24/09 Hi all, <Joey.> Many thanks once again for all your help throughout this build. <Welcome, happy to help out.> I have to say im just at my wits end with this thing. I have water in the tank now with some chromis and about 100lbs of rock (live). Got everything plumbed with 2 Quiet one 9000 in tandem (one on each end of a common manifold). What is troubling me is that I think I don't have enough flow. Well Actually let me rephrase. I think there's plenty of water "circulating" but the velocity of the flow I believe is way to slow. <A trait of spraybars. Even with great volume the flow is dispersed.> The main symptom is that after I've moved rock around the ensuing sand mess just settles all over the rock in a very nice even undisturbed layer of silt. Now if the flow velocity was adequate in the tank this wouldn't happen. Or at least not to this extent. The silt would be suspended in the water column and eventually get filtered out. So it seems that's I'm in the midst of learning yet another hard lesson in the world of marine aquaria. NOT ALL PUMPS ARE CREATED EQUAL!!! <Nope.> Well it seems that most pumps manufactured for the hobby are of a very low operating pressure. I'm seeing number in the 3 to 4 PSI range. That's seems rather odd to me and I'm not quite understanding the reasoning behind it. It seems that for most applications in a marine tank there is pretty significant pressure demand. Filters ,check valves, distribution manifolds, etc. So I'm amazed I even get the gurgling of water I do get out of my spray bars at 3 psi! I guess I just assumed that the pumps would be capable of sustaining pressures in the double digits at the VERY least. That would explain my situation. <The pumps in this hobby are what could be called low pressure. There is rarely a need in aquaria for higher pressure pumps. The pressure relates to flow, but is not the only variable. Higher pressure pumps give you higher pressure, but at the cost of flow and electricity. Lower pressure pumps will pump more per watt, just at the lower pressures.> So I'm faced with a difficult choice. I have to remedy this lack of flow or I think my tank will be a perpetual failure and a source of many many disappointments. But I'm at a crossroads. I've put an immeasurable amount of time and energy (not to mention money!!) into making this hair brained scheme of mine a reality with the spray bar idea and all that at this point I would really hate to have to abandon it but it looks as though that might be the situation. I feel I have one more avenue to explore before I put an order in for a bunch of power heads and just hang it up( I would consider that to be a failure but at least I could enjoy the tank even if it is with awful power heads in there and knowing I spent $500 worth of plumbing materials for absolutely no reason!!)I'm thinking that IF I take what i have now and mate it with a "high pressure" external pump (say a Turbo sea or little giant) it just might work. Here's what I mean: I would leave the sump and overflows plumbed as is. The only modification I would make would be to take the discharge of the existing return pumps off of the "spray bar" manifold and simply create 2 very simple 3 nozzle manifolds One for each end of the tank That I would set across the top of the tank. I would then individually plumb each pump to one of these. They would simply sit there and provided circulation of water through the sump and filter etc. The high velocity FLOW im trying to achieve would come from the existing spray bar structure however it would become a "CLOSED LOOP" of sorts. I would stick the suction side of the new external pump (via a suction hose of course) over the top of tank(nothing fancy at this point) and the discharge side would be plumed into the spray bars that were previously fed by the Quiet ones. If I got something in the 10-15 PSI range then I'm thinking the velocity of the discharged water would be significantly increased. I would then have good circ through the sump(provided by the Quiet one's and good flow/velocity in the tank provided by the "new closed loop" ! And of course my spray bar idea wouldn't be a complete waste! Also I'm thinking that one Quiet one 9000 is more than enough circulation for this tank at any one time. I'll leave them both plumbed in as described above but put them both on a timer. When pump b is on pump a is not. And vice versa. So they both get "exercise" and I'm providing a bit of a random flow pattern but I don't have both pumps running at once. <I really would not place these on a timer, startup is by far the hardest part for these motors. They are much better off running continuously.> Also the Closed loop pump would be running 24x7. So is my idea feasible? Or should I just chuck though whole idea and buy myself a handful of Koralias and call it a day? My fear is that I order the pump, plumb it in and find out that there is no change. I'll still have pathetic flow and I'll have to eat that pump as well. <My fear as well, this is a tough way to achieve perfect flow. Do also consider something like what is directed here: http://www.wetwebmedia.com/pbh2oret.htm with lengths of LocLine at each teed outlet. This will help quite a bit with the backpressure issue and allow you to adjust the flow easily.> I know the Powerheads will work but I just hate the idea. I suppose a bird in the hand..... but anyhow guys any help would be so greatly appreciated. Im just completely out of ideas for this. Praying for closure ! Joey <The diagram referred to above really is the way to go here. Scott V.>

Re: Hole Size - Approximate - theoretical Maximum Flow 1/25/09 Thanks Scott. <Welcome.> Yeah I just gave in a bought 4 Koralia 4's and 2 Maxijet 900's. I put the Koralia's at each corner of the tank (front only, top left , top right, bottom left, and bottom right) and then put the Maxijets on the rear pane with the Hydor wave maker attachment (circular thingy that rotates on the nozzle for random flow). Immediately the tank "Came to life" The rocks were cleaned of and the water was crystal clear within a couple hours and all the filters were absolutely plugged with debris. SO I guess I just have to call it a lose and a heck of learning experience. I did gain one thing though that at least I have very "even" return flow into the tank. This will ensure I have nutrient rich water going "everywhere" in the tank . Also when I add invert food and the like it will equally be spread out nice and evenly. The Koralia's don't look as bad as I thought so I guess I'll live with it. <The powerheads do also benefit your power bill compared to big circulation pumps!> Thanks again Scott for ally our help. Joey <Welcome, happy to help out, Scott V.>

Re: Pump Selection 12/28/08 Hmm, looking at the ocean runner. Is the 6500 too much for my 120 gal tank with 2, 1 inch drains with 4.5 foot head? Keeping marine and soft corals?? Or is the runner 3500 enough?? <I've erred here somewhat on the pump suggestions. With two 1 inch drains, you need to look at a pump in the range of 1000gph. If it's a little too much you can always throttle down the pump. I'd rather have a little too much pump than not enough. James (Salty Dog)> <<Mmm, not after it's pumped the water onto your floor... Better to get "just about the right "size", flow/pressure characteristics pump... And again, this amount of water cannot be conveyed safely through these two one inch inside diameter lines... would have to rely on siphoning (noisy, unreliable)... IF one line becomes occluded or the siphon stop (WILL happen), water will be pumped into the tank faster... overflow... RMF>>

Re: Pump Selection 12/28/08 Is it 1200gpm or 1200gph. <Wowsie, 1200gpm, nope is 1200gph.> Will my (2) I inch drains handle that at 4.5 foot head? <Probably not, depending on your head loss. James (Salty Dog)> <<Will NOT. I would re-drill, have two 1 1/2" drain lines. RMF>>

Re: Pump Selection: Scott V. input 12/28/08 Hmm, looking at the ocean runner. Is the 6500 too much for my 120 gal tank with 2, 1 inch drains with 4.5 foot head? Keeping marine and soft corals?? Or is the runner 3500 enough?? <I've erred here somewhat on the pump suggestions. With two 1 inch drains, you need to look at a pump in the range of 1000gph. If it's a little too much you can always throttle down the pump. I'd rather have a little too much pump than not enough. James (Salty Dog)> <<I would like to add for the benefit of all those reading that a 1" bulkhead will only flow 300 gph without siphoning (read: safely). Anyone with a couple of 5 gallon buckets, 1" plumbing, water and a timer can quantify this! Also, the pump may be throttled back, but there is also significant danger running an overflow to max. See here regarding redundancy and sizing drains: http://www.wetwebmedia.com/pbholessizeplace.htm. In other words to do this safely you will need a pump that will give you 300 gph at head height, seriously. This really is the problem with many of the overflows out there, the throughputs are just flat out too small! Scott V.>>

Re: Pump Selection 12/28/08 Question, if I do get powerheads (Hydor Koralia) and a submersible pump. What size pump (gph) and what size Hydor 3 or 4. Again with (2) 1 inch drains into a sump. A 4 foot tank by two foot. Which I will house marine and soft corals. Difficult to calculate the right amount of flow. <Mmm, not difficult at all, just strive for 10 to 12x flow rate for the size of tank you have. In your case, 1200 to 1400 would work well. Do read here and other related articles/FAQ's. http://www.wetwebmedia.com/ca/volume_3/cav3i1/Powerhead_test/powerhead_comp.htm James (Salty Dog)>

Re: Calcium Reactor Upgrade. Now: Overflow sizing, amount 12/27/08 Hello Crew, <Matthew.> Will 2 - 1.5" PVC Overflow drain pipes offer enough drain capacity for a 127 gallon 10" shallow coral holding system running a 4500gph hammerhead Reeflo pump? <Not even close for this pump.> or would you recommend downsizing to a 3000 gph dart pump instead? <These drains will barely handle the pump and not reliably. You will need many drains, or step up to 2".> The system will be housing sps frags on plug in eggcrate. There are 6 returns in the tank I figure ~700gph per return nozzle with the hammerhead. Have not purchased pump yet, will either go with 3000 or 4500 depending on the drains' capacities. Not exactly sure, just trying to get as much healthy sps flow as possible without running into system flow problems. <Either way you will need quite a large sump to handle this amount of flow. For throughputs you will get 700 gph or so out of a 1.5� and a bit more than 1200 out of a 2�. Do also consider the factor of overflow redundancy for the scenario of a drain line failing/getting plugged. See here: http://www.wetwebmedia.com/pbholessizeplace.htm.> Thanks for your input, Matthew <Welcome, Scott V.>

Re: Overflow sizing, amount 12/28/08 Scott, <Hello Matthew.> There will actually be 2-127 gallon tanks with a middle isle to walk in...Connecting the 2 systems will be a 115 gallon sump. So 2 holding tanks parallel to each other, with a sump (96x18x15") running perpendicular underneath the two tanks closer to the room wall..makes a C shape when looking from the top. I figure if I run a 3600gph dart pump on each tank, i will need to get 2-2" drain holes for each tank. <It will, but you may as well add one more drain to each tank. This will give you some redundancy should one drain become occluded.> So four 2" drain pipes will lead to the 115 gal. sump. I can choose to make the sump taller if needed to handle more water capacity..what do you think would be the best way to go about this...If 2-2" drains aren't enough for each tank, i could place 3-2" drains and connect them all to a much larger diameter pipe underneath and lead that to the sump...I have my tanks being made and ready to go on the 31st. <Do go with the 3 drain configuration.> Drain configuration I need to figure asap so he can predrill my drain holes properly/evenly. I do have a 150gal sps tank that is running 1540gph return pump and all of that is draining with 2 overflows connecting to a 1.5" drain pipe. Also a fish holding system running the same pump draining through a 1.5" drain. are you sure 1.5" only carries up to 700gph? <Absolutely positive. They do run a slight bit more depending on plumbing, but 700 is a safe figure. I have spent many hours of my life actually testing and quantifying this. One thing I did learn in the process is that pumps rarely pump nowhere near what we think they will in the real world! One pump in particular that does tend to stay strong is the Dart.> Being the case, I think 2-2" drains for the coral tank would be fair to handle 3600/2 minus a bit of head loss so were really dealing somewhere around 3300gph/2 = 1650 gph ea. 2" drain pipe. <I can give you a number here too, just for the heck of it! A Dart as a return with average head height and plumbing will be in the neighborhood of 2500-2700 gph.> Your thoughts again appreciated. Thanks, Matthew <Welcome, a pleasure to assist. Scott V.>

Re: Overflow sizing, amount 12/28/08 Scott, This is great..Thanks for your help. <A pleasure to assist!> Will go with 3 - 2" drains per tank. That makes me feel more comfortable actually...the last thing i want to have happen is the whole thing to spill over...that would be a fun day. <I can attest, I just returned home to find out an acquaintance had a 500 gallon tank burst today.... believe me the water belongs in the tank, not on the floor!> As far as preventing a wrasse or something from going overboard would you recommend rubberbanding some of that black plastic net stuff around the pvc's? <You can, just brush the stuff clean frequently, it can have a surprising impact on flow.> I am making the sump a bit taller 18" instead of 15" to hold power outage water. <Good idea.> As far as sump design goes, I really don't need any baffles or specific chambers right? <With the amount of water you will have running through you will need some baffles as bubble traps if nothing else. See here: http://www.wetwebmedia.com/ca/volume_3/cav3i1/Baffles/bafflesart.htm for an easy way to do this while keeping it adjustable. Do also consider partitioning off a section as a refugium, you have some room to work with here.> I really just want to place a big ASM G4x in there with a nice cal. reactor and that's about it. Am i missing anything important? <A refugium really is worthwhile. See: http://www.wetwebmedia.com/refugium.htm for the low down on all the benefits.> Filter sock chambers perhaps for the drain lines? <Not a complete necessity, but nice to do. Just buy a bunch, change them often and then wash the lot at one time.> Otherwise i just envision a plain and simple rectangular sump box. I want to place a pump on each side of the sump under each table, the skimmer would be right in the middle of the sump so i can easily walk up to it and grab the cup for cleaning and not have to reach under the table. Does this configuration make sense to you? <If you do add a refugium you will want the skimmer at one end with the refugium either in the middle (leaving the returns on the opposite end of the skimmer) or the refugium at the opposite end of the sump. The idea is to have the water leaving the refugium not flow through the skimmer.> -Matthew <Have fun, Scott V.>

Re: Overflow sizing, amount 12/31/08 Scott, <Hey Matthew.> Here is what design I came up with (see attached jpg). Since there are 3 overflow's per tank. Each far side pvc overflows into their refugium ~1000 gph each. the remaining 4000 gph flows into the skimmer section in the middle. None of the refugium water is skimmed or baffled...how do copepods get through a bubble trap? <Heee, float or swim!> Therefore...designed without any baffles for flow coming out of the refugium. Figure skimmer would be making the most amount of micro bubbles, will add baffles in skimmer overflow area. The last area is just reservoir water before entering pumps. Any thoughts on this design?? <It all sounds fine. My only concern is (and I may be misinterpreting your graphic) it looks like you are combining drain lines from 4 to 2 lines coming into the skimmer area. If this is so you will want to step this combined line size up to 3' line to keep true redundancy with this.> Thanks, -Matthew <Welcome, you are well on your way! Scott V.>

Re: Overflow sizing, amount 12/31/08 Ahh thank you, was just about to ask you about the drain lines being connected. To be safe, i will make each drain independently flow into the skimmer area, 4 lines dropping into it. Thanks for all your help. Will let you know how it goes the next week or so. Im picking up my tanks today! -Matthew <Welcome and congratulations! Scott V.>

Re: Overflow sizing, amount 1/1/09 Scott, Thought i would send you a pic of my new coral tanks, these are beauties. Would get started on the plumbing but i don't have my sump yet and all hardware shops etc are closed today for new years. happy new years, Matthew <Wow, very nice setup! Do enjoy, have a good new year! Scott V.>

Re: Overflow sizing, amount 1/14/09 Hi Scott, <Hey Matthew.> I got one of the coral holding tanks up and running so far...the tank works fine with the 3 - 2" overflows, had a couple of 3/4" bulkheads leak but were quickly fixed with a slight turn of the wrench. My only concern at this point is reducing bubbles coming out of each of the drain pipes in the sump, because the water is flowing so fast down the tubes..it really churns air/water making lots of sump bubbles. Is this a matter of angling the drain pipes right? or adding a specific overflow piece to reduce the water tumbling down to the sump? <A few methods. For some the addition of filter socks eliminate the issue. As you mention above, running the pipes at a slight angle can give you big results, just do not run it at too much of an angle. It can lead to the problems associated with horizontal runs in the overflow line. Something like 15-20 deg from vertical will do the trick, it does not take much. Otherwise it comes down to playing with the baffles in the sump. This is quite a lot of water you are moving through it and may take some trial and error with the baffles until you find what works with your particular setup.> Thanks for any ideas -Matthew <Welcome, I hope this helps. Scott V.>

Re: Overflow sizing, amount 1/15/09 I think what im going to do is.. drain the tank, handsaw off the pvc drains underneath, remove the bulkheads, replace the bulkheads, add 2" inserts x slip and add 2" flex drain tubing, That's how i have my reef configured, I think this will eliminate majority of bubbles crashing down because I can angle tubing much better, I have no flexibility with current pipe drainage. Also this will allow me to disconnect in future with greater ease if necessary, a versatility thing. I don't know why I didn't do this before. I will let you know how it goes. Thanks -Matt <A sound plan, do let us all know how it turns out. Scott V.>

Re: Overflow sizing, amount 1/24/09 Hi Scott, <Matthew.> I am re-plumbing a 60 gallon acrylic rectangle reef tank standard 4 ft long. It does not have built in overflow, I am currently using a CPR siphon overflow which I am going to take out... my question is... as far as designing an overflow box to be installed in the tank, I am thinking of placing an overflow tower in the center back within the tank. Is there a formula to determine how many inches deep the slots need to be and how wide? <No particular formula, but 1.25-1.5" deep works well at these flows from my experience. For width 1/4" is works fairly well if you are using a router, a 1/4" bit and cheapo dovetail jig will give you perfectly cut teeth in no time. If you are saw cutting the teeth any width you want can work, but if you go too small keep in mind the teeth get weak. A small bump while cleaning the tank can knock the things off.> I want to run a T4 Poseidon 1225gph @ 3ft head pressure and use a 1.5" drain to the sump. Do you have any idea how many inches LxW for the overflow tower? <A few inches front to back, enough to accommodate the standpipe and bulkhead is all that is needed there. For width I would make it 12-15" myself. This will give you water flowing right about 1/2 way up the above listed teeth. For this pump you will want two 1.5" or one 2" bulkheads, double that for any kind of redundancy.> I would guesstimate something like 6 inches length by 4 inches wide footprint, and something like 2 inch deep slots 1/4" wide. Any ideas? <I would make it wider, at 6" it will flow over the top at this flow.> I appreciate it...The other 300 gallon system is turning out great, i just had to add a couple of baffles to the sump for crash chambers which slowed the water down perfectly for the refugiums. Will send more pictures when electrical outlets get installed etc.. next week.. <Sounds good!> Thanks a lot for your help on that. <Happy to assist.> Also took out rigid pvc and used 2" drain tubing with much much better results..less bubbles, no more vibrating pipes... <Great!> Thanks, -Matthew <Welcome, have fun, Scott V.>

Re: Overflow sizing, amount 1/25/08 Cool, I think i will do that 12" x 3.5" to fit the 1.5" bulkheads down there. On my other reef setup, i am using two overflow towers 6" x 4" and 1.5" bulkhead for each tower, underneath they connect to 1.5" pvc tee'd together and exit through an insert connected to a single 1.5" tubing which leads to the filter sock and this pump is 1540gph...no problems at all for flow. Im thinking I could get away with that for this 60 gallon setup with a large enough overflow as you say and teeing together 2 1.5" bulkheads underneath the tank into a single 1.5" tubing to a sock just like my other reef. <This can work to some extent because there will be a water column that builds up above where the two lines are teed together. The problem with this is you lose true redundancy.> Also, was wondering about using my old Knop c reactor for this small setup, is it possible to hookup a standard regulator to a paintball sized co2 tank? I think they have the same hookup as the 5lb or 10lb tanks but wasn't sure...maybe you know. <Yep, they are the same standard ASA threads. You will of course have to swap them more often, but these tanks are worlds cheaper, there is no reason to not own two or three. If you are a paintballer you likely have a few already. Some argue against this on two points. First is the purity of the CO2. Well, I can assure you the CO2 will come from the same source either way. The other point is the cost of fills, a somewhat valid argument. It will likely cost you $3-4 to fill a 20oz tank, while $5-7 is normal for a 5lb tank. If you already have a 20oz or two it does make sense to use it, at least until you get a larger tank.> -Matthew <Scott V.>

Re: Overflow sizing, amount 2/4/09 Greetings Scott, <Hello Matthew.> A couple of things i was thinking of... If i were to use 1.5" inlet strainers for the intake of the dart recirculation pump, could i place liverock around them so that they are not obvious..and couldn't a fish die and get stuck on one of those and be a hassle to uncover/remove live rock in an sps tank? <Is a risk.> Or is the intake flow greatly reduced by having two 1.5" intakes therefore reducing strong suction problems with things like anemones etc.... I can only logically see the strainers being placed smack center of the tank bottom evenly spread apart.? <Having two inlets does reduce the velocity quite a bit. The scenario of the dead fish is not much different than the thing being trapped within the aquascaping anyhow. Turn the circulation pump off and then get creative about getting it out!> The returns i would want to place them in the exact same spot as the strainers so would i place the returns evenly center instead and strainers slightly near them? <You can, although I try to get intakes and returns a bit farther apart. It is too easy to just get the water circulating in just that area.> I will not be using any sand in this system, just coralline bottom. How tall do the returns need to be within the tank... i want to maximize flow in the entire tank not just the upper portions...was thinking of coming up from the 3/4" bulkheads with 3/4" pvc and splitting each of them with a tee and adding a Y loc-line fitting on each side to create 8 outflow nozzles total + 2 nozzles from the return pump from a SCWD coming out of the overflow side near the top. <Will workout, the PVC and LocLine makes things easily adjustable should you need or want to tweak it.> How deep should the overflow holes be to get the best looking fill in the tank (60" x 28" x 22"), i only want to see about 1" of air from the top of the tank. You think 1.5" or 2" would be ok? 1/4" wide slots...overflow rate is 1500gph. <Let me know how long and wide you ended up making the box and I can get you really close.> And just to double check, the system will only have 2 400 watt 14k lights, will a 1/4HP chiller be sufficient or do you think a 1/3hp might be necessary? <Depends on the ambient temp, but I would opt for the 1/3 here.> Im looking into Current USA chillers, maybe Pacific Coast Imports, or Arctica, any recommendations? <All good choices in my experience.> Thank you again, Matthew <Welcome, Scott V.>

Plumbing a 150G 8/13/08 Hello, <Carlos.> Started getting into plumbing a 150 gal tank. It currently has 4 bulkheads (2x 2" and 2x 1.5"), I am using the 2x 2" as drains to my sump, which are both reduced to 1.5" pvc pipe to sump. I would like to have a return pump (mag drive 36) sending water from the sump into a manifold of 1" pvc with .5" teed nozzles for a closed loop, I was thinking 8 outlets. <Eight should be about right.> The head is about 4ft from pump to both return 1.5" bulkheads, which is wyed and split to each bulkhead. So the pump would return about 3000 gph (maybe closer to 2600ish gph due to 2 elbows and wye). <More like the latter.> Reefcentral.com's calculator says a 1.5" drain will drain about 1300 gph. <Nope, more like 750 or so safely.> So the question is will I have enough flow from tank to sump and sump to tank through the manifold to have an effective manifold/closed loop? <The amount of flow is fine, although quite a bit to manage through a sump.> Are my drains going to be able to handle the flow? (I have a feeling I might have to go with 2" pvc for drains.) <You got it. You will need two 2' drains to handle this, I would suggest a drain or two more for redundancy in case one fails.> Carlos Bica <Scott V.>

Re: Plumbing a 150G 8/14/08 If I added another drain wouldn't I be draining more than my pump could handle? <No, the idea with the drains is that they are either placed where or have some sort of weir/box that will only drain water above a certain level in the tank. You can out pump the drains, but not the reverse. The exception is a submerged drain run on siphon, if your pump stops or flow is reduced the drain may have the ability to flood the sump, not to mention the possibility of the siphon failing and flooding the tank. More or larger drains gives you the ability to get more flow through the system, not utilizing all that flow capacity will allow you to have some margin of safety should one drain fail. More info on this at the link below/related FAQs. Scott V.> http://www.wetwebmedia.com/ovrfloboxfaq3.htm

Re: Plumbing a 150G 8/15/08 Gotchya and thanks a lot. <Very welcome.> After a lot of deliberation I am just going to dedicate the Mag drive 36 to the closed loop system and slow down my drain/sump flow rate to probably 1000 gph if not less. <Really a better, easier to implement plan.> I was trying to consolidate the two (closed loop/sump) but alas that doesn't seem feasible or smart/safe in flooding terms. <It is doable, but a headache IMO.> Thank you very much and your website rocks, been reading for a couple years and have been able to find answers to about 99% of my questions. Finally taking the leap, wish me luck. Ciao <You will be fine. If you run into issues, do write back. Scott V.>

Loud Overflow (Another Overwhelmed 'Mega' Drain) -- 07/17/08 I have recently set up a 90 gallon reef tank with a central inside the tank standard Mega overflow kit. <<As yes, the grossly overstated 1-inch overflow kit>> It drains through a one-inch bulkhead into a 30gallon sump below the stand. I have been doing a lot of research concerning Stockman, Durso, and Hofer gurgle overflow pipe constructs that supposedly will quiet down the gurgling noise. <<Will help'¦as long as you aren't simply overcoming the drain with too much flow. Regardless of what may be stated in your kit, trying to run more than 300gph through a 1-inch gravity drain is trouble>> I am still confused which one will work best for an inside the tank overflow which is 24 inches tall. <<Differing means to the same end. All will probably elicit a change'¦finding which one fits and performs best for your situation/setup will take some experimentation>> I am worried about handling the outflow. <<'¦?>> I have a Gen-X pcx-40 pump <<Yikes! Unless you have a ton of headloss or this pump is throttled way-back, it is way too much pump for a single 1-inch drain (see my earlier comment re)! You have a dangerous potential for flooding, and as you have discovered, noisy siphon effect going>> which I plumbed into our crawlspace for noise control, and the standard design of the Hofer gurgle pipe only handles 5-600 gph. <<In reality this is plenty'¦the concern is over how much flow your 1-inch drain can safely handle (300gph)>> I was trying to determine should I increase the size of Hofer gurgle to 1.5 inch and 2 inch pipe, does it need to be taller than the design on their website which is only 5 inches tall and then extend the air tubing above the water line, or is there a better option for noise control that can handle the overflow? <<I would follow the recommendations of the designers'¦and visit/query the reef forums for others input re their design modifications, if any. But the real issue you need to address is flow rate. As stated, you just have too much water being pumped to the tank for the 1-inch overflow to handle. I would suggest you downsize the return pump (best option), or at the least install a gate valve on the output side of the pump to reduce flow to that which the drain can safely handle'¦even with an aftermarket 'gurgle pipe'>><RMF would have another drain line drilled, fitted.> Thanks, Mark <<Good luck with your plumbing project. EricR>>

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