Plumbing Questions

[John Wilson]

As a novice to all of this, I continue to have questions.  The system I'm building is flood and drain with a 500 gallon fish tank with a 1:1 grow bed ratio.  First, I'm planning on using 1/2" delivery pipe and 1" drain pipe.  The 1/2" was based upon the recommendation in Sylvia's book.  Also, per her book, I'm planning to not cement any of the joints.  This part especially concerns me.  Any thoughts on either of these two points would be appreciated.

[Jonathan Kadish NYC AA Chair]

The size of the pipe has more to do with the flow rate from your pump. With a 500 gallon tank you will want something that can at least pump the volume of the tank once an hour and more if you are pumping to any height greater than a few feet. 1/2 inch can do that but when it comes to sizing pipe, the more restrictive you are, the more friction there is, so the less efficient the pump operates.

Over 100 feet of pipe

1/2 inch at 480 gph will have a head loss of 49.5
3/4 inch at 480 gph will have a head loss of 12.3
1    inch at 480 gph will have a head loss of 2.9

So you can see how much more friction there is in the 1/2 inch pipe. This can also make the pump fail sooner.

You are probably not pumping through 100 ft of pipe but 3/4 inch may be a better choice from a long term perspective. You will also want to provide multiple outlets in the grow bed so it is not gushing like a hose out of just one. As for the Joints you will want to cement the joints or they will leak, especially where you are just coming off the pump. Unions are critical where you see the need to disconnect for maintenance but glue where leaks would be a concern.

Your drain depends on how you are draining but go larger than your pump and go even larger for the overflow.

I did a video on plumbing when I just started out on my channel http://www.youtube.com/aquaponicsnyc

[John Wilson]

Jonathan, Thanks for the input.  The cement thing did worry me since I've done quite a bit of plumbing work at home through the years but I had never worked with small water pumps so I thought maybe that was why you could get away with no cement.  As for the pipe size, since I'm only pumping about 50 feet in total, I'll have to give that some thought.  Thanks again.  P.S. - If you any recommendations as to specific pump brands/models, I would welcome the input.

[wes]

I personally don’t recommend a 1/2 pipe for water flow the pipes over time build up a coating and the 1/2 seems to gunk up easier, I ran a small 1/2 pipe run off of my larger main system via a smaller pump to my two 55 gal aquariums and it seemed to be losing flow after about a two month period so i turned the pump off for a few minutes then back on and allot of crud and gunk came out of the pipe after doing that an the flow was somewhat better but not like it was when I first started the pump up for the first time. I have a 300 gal tank and a hybrid style system that one larger pump is running and I used 1 inch pvc and its working great but i am pushing all my water up and letting it all drain back to the starting point so I need the good size pipe for this type of setup. The smaller pump is in the sump with the larger one and it just feeds the two aquariums that’s all it does.

 

[Jonathan Kadish NYC AA Chair]

Yeah bio-fouling is something to consider as you make your design... yet another reason to size larger.As for the type of pump... I'm no expert but there are some out there who will sell you a pump. I just did a workshop at Aquatic Ecosystems and they were awesome in helping with design and equipment. You don't have to do a workshop either to get that help. Call them up and an actual person who is very knowledgeable will walk you through the choices.

[TCLynx]

Definitely go larger with the pipe.  1/2" might be ok for a tiny aquarium system or where you are only talking about a few feet of pipe from the fish tank up to the grow bed on a single IBC system or something but I still almost always upsize my plumbing.

The plumbing from the pump to the grow beds should be at least as big as the plumbing fittings on your pump or BIGGER.  My 300 gallon system uses a little 50 watt pump but because I'm trying to drive a special valve with it, I upsized the plumbing from the pump to the valve to make sure I always have max pressure and flow for proper operation.  Anyway, that pump has 1" fittings and delivers really good flow but I still often upsize the plumbing if I want to max out the flow it will deliver.  And then my drain lines will be bigger than the pump line.  Most of my grow beds doing timed flood and drain have either 1 1/2" stand pipe drains or 1 1/4" stand pipe drains.  Then if more than one bed is sharing a drain back to the fish tank or sump tank, I usually wind up using 3" or 4" common drains.

For a 500 gallon fish tank what pump would I recommend.  Well I suppose I need to know if you will do timed pumping or constant pumping.  I'm kinda partial to pumping a huge amount of water around to keep the water quality and aeration maxed out.  For 300 gallon and smaller systems I like the Quiet one 4000 pumps.  When I go to bigger systems, I've been mostly using the Danner MD18 pumps for systems of probably up to 800 gallons of fish tank.  If going bigger than that, an inline energy efficient pump should probably be figured out based on system specifics.

[John Wilson]

I just turned on my system yesterday and as normal I still have issues.  I ended up using 3/4 inch delivery pipe and I bought a Danner MD 18 pump based upon the group's recommendations.  All of my runs are located three feet above the water surface of my tank.  I'm running a total of 50 vertical feet comprised of two runs.  One run has seven outlets serving seven GB's and the other has six outlets.  I  built bell siphons for all the grow beds and some are working and some aren't.  I'll continue to work on those this week.  My biggest concern so far is the lack of water flow for the GB's towards the end of each run.  Here are some of my questions related to this issue.  First, on my pump, I have it standing with the outlet (the male 3/4 in. pipe fitting) facing straight up towards the surface.  Is this correct or does it not make any difference?  Many of the pictures of this pump have it lying with the outlet coming out horizontally.  Secondly, and I hope this isn't a problem, could it be the size of my pipe.  I would hate to have to redo all of my plumbing but I will if I can't get this corrected.  And finally, could the fact that I have 13 outlets being affecting the flow at the end of each run.  Thanks.

TCLynx said:

Definitely go larger with the pipe.  1/2" might be ok for a tiny aquarium system or where you are only talking about a few feet of pipe from the fish tank up to the grow bed on a single IBC system or something but I still almost always upsize my plumbing.

The plumbing from the pump to the grow beds should be at least as big as the plumbing fittings on your pump or BIGGER.  My 300 gallon system uses a little 50 watt pump but because I'm trying to drive a special valve with it, I upsized the plumbing from the pump to the valve to make sure I always have max pressure and flow for proper operation.  Anyway, that pump has 1" fittings and delivers really good flow but I still often upsize the plumbing if I want to max out the flow it will deliver.  And then my drain lines will be bigger than the pump line.  Most of my grow beds doing timed flood and drain have either 1 1/2" stand pipe drains or 1 1/4" stand pipe drains.  Then if more than one bed is sharing a drain back to the fish tank or sump tank, I usually wind up using 3" or 4" common drains.

For a 500 gallon fish tank what pump would I recommend.  Well I suppose I need to know if you will do timed pumping or constant pumping.  I'm kinda partial to pumping a huge amount of water around to keep the water quality and aeration maxed out.  For 300 gallon and smaller systems I like the Quiet one 4000 pumps.  When I go to bigger systems, I've been mostly using the Danner MD18 pumps for systems of probably up to 800 gallons of fish tank.  If going bigger than that, an inline energy efficient pump should probably be figured out based on system specifics.

[TCLynx]

50 Vertical feet?  as in you are trying to pump 50 feet up?  Are your grow beds on the roof or something?

I didn't even thing that pump would pump that high?  I'm hoping you actually mean 50 horizontal feet.

Upsize the pipe from the pump up to at least your first Branch.  3/4" pipe is the minimum size pipe you should connect to that pump and you can get some more flow by using larger pipe for at least some of the run.  I think up sizing the pipe will help greatly in getting enough flow to your beds.

[John Wilson]

Right, 50 was supposed to be followed by horizontal and not vertical although roof top GB's could be the start of something interesting.  Would you think that 1" would take care of the situation.  Also, do you have any strong opinions on 90 degree elbows versus two 45's?

TCLynx said:

50 Vertical feet?  as in you are trying to pump 50 feet up?  Are your grow beds on the roof or something?

I didn't even thing that pump would pump that high?  I'm hoping you actually mean 50 horizontal feet.

Upsize the pipe from the pump up to at least your first Branch.  3/4" pipe is the minimum size pipe you should connect to that pump and you can get some more flow by using larger pipe for at least some of the run.  I think up sizing the pipe will help greatly in getting enough flow to your beds.

[TCLynx]

I would probably do 1 1/2" from the pump up to the first branch and then I would probably do 1" for the long horizontal run and just drop to 3/4" at each grow bed.

A 90 degree sweep or two 45 is better than a hard 90 degree elbow.

[John Wilson]

Here's my update.  I followed your suggestion with regard to piping except for the 18 foot run in the front part of my GH.

Just finished over lunch and turned the system back on.  It looks like all systems are go except I'm still a little disappointed in the amount of flow.  I have a branch off of my back run which I was hoping to use but I'm skeptical if I'll have enough flow.  While the current runs are roughly at 2 or 3 foot head, extra run of ten feet is up another couple of feet.  However, all and all, it's looking good.  I've got 12 of my 13 bell siphons working.  I just added ammonia earlier this evening for the first time using an online calculator and a guess on my total water volume.  I guessed 800 gallons and I put in 3 5/8 fluid ounces of ammonia from ACE.  Ran double checks on my ammonia levels and both times it read 4ppp.  Thrilled with that.  My PH, which I tested at roughly 7.6 when I had only water and no solite, just tested still at 7.6.  So I think things are looking up.  I plan on continuing to add ammonia each day until I see my nitrites starting to show up.  Thanks for your help.  I'll try to take some pictures this week.

TCLynx said:

I would probably do 1 1/2" from the pump up to the first branch and then I would probably do 1" for the long horizontal run and just drop to 3/4" at each grow bed.

A 90 degree sweep or two 45 is better than a hard 90 degree elbow.

[TCLynx]

If your ammonia is at 4 ppm

DON'T add any more till you see the ammonia start to fall down below 1 ppm.  Otherwise you will have sky high ammonia levels that will probably stall out the bacteria that take care of converting the nitrite to nitrate.

And for future doses I would probably recommend smaller doses than your initial dose.  Dosing to between 1-2 ppm of ammonia is adequate for cycling up.  More is not necessarily better.

[Bob Rogers aka The White Lion]

I would also look into using PEX Pipe for plumbing your system. It is very flexible and the fittings do not use any glue. Once you have made your connections and tightened the fittings, you will never experience any leaks. You can also use the different colors to distinguish your different water flows. One color for the outflow and one color for the inflow or return line. Its great stuff to use and very easy to work with, with the added plus of not having any potential contaminates.