Treated CPVC BAD?  Justin Explains the Difference Between CPVC & PVC and Other Acronyms 10/23/05
<Paul> 
In the freshwater hobby I've used CPVC extensively. I've read that in CPVC the C stands for chlorinated and this has raised havoc for the livestock in reef systems.
<Mmmm not that I have ever heard PVC is poly vinyl chloride but is an inert substance that doesn’t leech back into systems. CPVC is used in conjunction with copper tubing and as such is set up with its measured diameters being the outside rather than PVC which is inside diameter. The extra C at the beginning is just the way to differentiate between them. I have used CPVC and PVC extensively for a very long time with no side effects in SW systems.> 
I also have misgivings about the gray PVC and more importantly at this time, The PVC marked DW. This stands for drain water. I've been told that it has antimicrobials mixed in its makeup. Is this true? 
<A few calls to plumber friends in the PVC business, and a company who sells PVC styles have yielded no information of that kind. I have used standard PVC pipe at up to 8 inch diameter before and seen no mention of such agents put on before hand, though PVC is toxic when it is being mixed.> 
The DW PVC is the only 4" or greater diameter piping I have found. 
<Standard PVC comes in at least up to 8” here, try calling a home improvement store or a local plumbing contractors store who carries larger piping etc for such needs.> I really need them for Skimmer and filtration component parts. I guess it boils down to; which of the types of PVC do you specifically have experience with and are there any types you would consider unsafe for reef aquarium use?
Thanks for your time
Paul
<Well PVC and CPVC are fine for usage as long as you let the glue and primer cure for a while before hooking it up. I have run it as soon as the glue is hard (around 1 minute) without waiting in emergencies, but a 12 hour wait guarantees the bond at the joint is as strong as possible before you subject it to pressure. In most setups simple PVC is fine, though CPVC is nice as it takes up a little less space; however, you do loss some flow and add a bit more pressure for the pump to overcome. Buy the same sized pipe that your pump uses without needing adapters or flow restricting couplers from one size to another. The longer the run at one size the easier it is on the pump and the longer your system runs without maintenance.>
<Justin (Jager)> 

Lost Emails and Pipe Sizing
Don't know what happened to my e-mails but received no response, so here goes one last try.
<We didn't lose you Scott, we get a lot of mail to answer!>
150g tank, dolphin return pump, 1 1/2" tubing from pump to Y fitting, hoping to get 2000gph using six nozzles off of manifold along with three 1 1/2" overflows.
Question is what size pipe to reduce to coming out of the Y fitting to serve as the manifold , 1" (with 3/4" nozzles) or 3/4"(using 1/2" nozzles). Thanks for any help.
<Total flow rate of six outlets needs to total 2000gph or slightly more. Use plumbing sized to accommodate this. (Pipe has a known flow rate at known pressures).  I don't keep these floating in my head, but they are to be had on the net (flow charts at plumbing manufacturers, etc.). My own feeling is 1 1/2" pipe will be reduced too much with two 3/4" lines, no matter how many outlets they have. I would go larger and step down as needed or w/valves on flex/ball fittings.  Craig.>

Plumbing...
Craig and the rest of the Wet Wizard and Masters Crew!
As always let me thank you most sincerely for your help. You have been an invaluable resource and unlike my LFS have kept me from getting discouraged by the amount of learning and researching that getting into this hobby requires.
My praise is not mere flattery but in response to the genuine enthusiasm the WWM crew seems to have for everyone associated with this hobby. Thank you from the bottom of my heart!
<Our pleasure!>
I have moved to the plumbing phase of the setup of my 90 Gal reef and I had a few questions for the crew.
For a 90Gal with a decent to high flow rate through a refugium/sump using two back wall weir enclosed bulkhead inputs and two rear wall 90ell style outputs what would you recommend for flow rate, diameter pipe and pump?
<I like em' big, 1 1/2" - 2" overflows. Pump and turnover dependent on inhabitants. Softies, etc. 10X turnover, LPS/SPS up to 20X. Pump depends on head, needed flow rate, plumbing restriction, etc. Very individual. You need to oversize substantially for your needs.>
>My idea was to use two 2" bulkhead inputs Teed together into a 2" pipe which would empty into the input chamber of the sump (should the combined pipe be a large diameter than before the Tee or is the 2" to the sump ok?).
<Absolutely or use two separate bulkheads and lines to the sump. (2")>
On the output side I was planning on using 2 Mag-Drives for return with a float switch on both pumps and anti-siphon tubes on the return lines which I thought would be 1.5". (Comments, suggestions?)
<No need for float valves or two pumps. One well sized pump and a gravity fed overflow/sump will work fine. Use siphon breaks in the refill lines at water level (same level as the top of the overflows) so the amount of water that can siphon into the sump is fixed. I prefer gravity to float valves, etc. but sometimes it requires more work as it is less automated.>
I thought that this would give me a reasonable flow rate, protect the pumps and provide some redundancy in case of a pump dying or a bulkhead to sump line clogging. The anti-siphon and the reason for the weir style upper back wall mount is that I do not want to deal with the typical overflow ... in that my sump does not have a large amount of empty volume in case of power outage. I designed it to run mostly full with about 7 gallons of spare capacity.
<Make sure only 7 gallons is in the lines, above overflows. Bulkhead lines flow pretty good, they don't tend to clog. What if one of the float valves gets some gunk in it and doesn't shut off?  I hate that! Best to design around it.>
For further water flow (I want to avoid the use of ANY powerheads) I was very interested in creating a closed loop system similar to the one at Reef-Eden http://website.lineone.net/~espsrg/diy_6.htm) -- Except (and here is where my question is) -- is that I would like to be able to drive like 3-4 3/4" lines off of one pump. Would you use 1 large diameter pipe as the intake and then split the lines up with a manifold on the output side of the pump or would you keep the lines separate with a manifold on both sides of the pump? Do you think an Iwaki 40 could handle roughly 4 3/4" line outputs with about 4 ft. of head or would I be better off using single pumps on each line?
<You can drive it with one pump and manifolds on both sides, but oversize the plumbing, especially on the intake side. The pump required depends on too many factors not included. You need to know head height, plumbing size, etc. I advise over sizing substantially both pump output and pipe size.>
Once Again I would like to thank the Crew for so much help and such a wonderful site!
<Hope this helps out.  Craig>

Re: Overflow Question
Thanks!
Just to clarify, there won't be any no problems (noise or otherwise) with having the 3 2" bulkheads installed on the back wall of the tank, at the water line. With this configuration, no overflow will be set up. The water will free flow through the bulkhead into the vinyl type pipes behind the tank, into the sump below.
<Should be sweet, esp. with vents (similar to Durso) just above the vinyl pipe fittings. A tee with riser and a drilled cap (1 - 1/4" hole) works great. I like ells in the tank, but they can introduce water noise.
Will 3 2" free flow piping handle 3000 gph?
<Sure. To double check look at the overflow rates of aftermarket boxes with 2" pipe. My vats use 2" overflows and they handle around 1400-1500 gph +/- .  Craig>

Pipe work/plumbing
I am setting up a small 10 gallon refugium with gravity return from water surface and would like some advice on piping does it have to be of a certain grade and where can I get it cheap in the UK can I get it from a plumbing shop or does it have to come from aquatic retailers?  Thanks Bob.
<Hello! You can use regular household polyvinyl chloride (PVC) available at your local DIY or plumbing shop. They will also sell the glue you will need. Bulkheads can also be obtained from these shops or from a pool and hot tub supply. Have fun! Craig>

ABS pipe.
Hi Bob,
firstly I would like to thank you for enlightening me on the amazing world of marine life/biology/chemistry etc, through your excellent book the conscientious marine aquarist.
<You would do the same>
secondly my question, are there any special requirements for the pipe work used in marine aquariums??? or can ordinary abs plastic fittings be used?
<Yes>
thanks for your time in answering all these questions, you are a true scholar & a gentleman.
thanks again Brent......UK.
<As we aspire to be. Bob Fenner>

Re: abs pipe.
Dear Robert,
thank you for your speedy reply to my last letter, but I'm afraid I have been left a little confused to your reply. when I asked the question 'are there any special requirements for the pipe work used on marine aquariums??? or can ordinary abs plastic fittings be used? your answer was yes. was that a yes to normal abs pipe or yes to a special grade pipe work.
<Sorry for the lack of clarity. The response is indeed "yes" to both. Please read here: http://www.wetwebmedia.com/pbfaqsmar.htm >
sorry for the confusion and your great work is much appreciated.
Brent.....UK
<Be chatting my friend. Bob Fenner>

Schedule 80
Dear Rob,
Hope you can help me with this. Went to a hardware shop looking for schedule 80 piping. The guy offered me one with the same thickness but with the designation AWG or AWS <Mmmm, why schedule 80... rated for 800 PSI pressure... in pet fish (let alone fire hydrant construction) you don't need this> he said that schedule 80 was double the price and is useful only for chemical environments. Should I be on the safe side and specify schedule 80 or the one he offered is sufficient.
<Schedule 40, even 200 is fine...>
The reason why I wanted a thicker diameter is I will be laying the pipes under concrete floor, so need a stronger walled pipe, that will not flex.
The smaller diameters are fine... they're strong enough... and cast in concrete, very unlikely to have problems. I would use schedule 40. Bob Fenner>
Thanks in advance and a Happy new year to you!!
John
Http://www.marineangels.com

PLASTICS IN THE AQUARIUM
Dear BOB and WWM Crew,
<Good morrow>
I am constructing my fist marine aquarium, I have the tank, the sump etc. But up to this moment in time I am reluctant to purchase any pipe work and start commissioning the tank.
My problem is the usual; ask 100 people a question and you get 100 different answers.
Do I use ABS, PVC, Polypropylene or other pipe work. People say to me get food grade piping, well that's all very well until you ask the retailers, they don't know. From my aquatic stores I get different answers as well.
<I have used "regular" (generally schedule 40, but at times some 80 for valves, unions) PVC tubing with success for many years>
Basically I would like to know which plastic material is the most chemically inert. I don't want to poison my fishy guests. Also I've been told that pipes from builders merchants are not safe because they put some kind of fungicide/pesticide in the pipe during manufacture to keep algae etc. at bay in the pipes. 
<Not... the material is used in all sorts of "human-impacting" applications... it is safe enough to carry water for your use...>
I have also been told that some plastic's fail mechanically when in contact with salt water for long periods of time ( My girl friend would kill me if she came home
and found 150 gallons of salt water on the carpets).
<This last part I do believe... make sure and prime AND solvent each joint... and test before she's there>
I have been sold some grey polypropylene pipe by my local aquatic store. It is standard 32mm
(1 1/4 inch) pipe that is sold in the builders merchants as sink basin waste pipe.
Also I read on a KOI carp site that you shouldn't use polypropylene, no explanation why?
<More money, no better in all respects than PVC...>
Could you please help ?
Many thanks,
JON
<Get around to other hobbyists' set-ups, maybe call and chat with some folks in the aquarium service business in your area... PVC is fine, what I would use. Bob Fenner>

Plumbing
I want to hard plumb my filter system. Does it matter what type of pipes I use? Will the glue that you use to put the pipes together harm the fish? Also, what type of UV filter would you recommend for 100 gallon tank? Thank You!
<See the "Plumbing" pieces on the Marine and Pond Indexes on our website: www.WetWebMedia.com... most folks use PVC or ABS of the various formulations used... and the solvents have no effect as they're "gone" when the plumbing is in use... some slight toxicity from these plastics, no big deal. UVs are also covered on the FAQs section of the same name on the WWM site. Happy reading. Bob Fenner>