Backyard Aquaponics
A place to discuss aquaponics

Ok I am still toy with getting my system to flow correctly and having SEVERAL problems so I have figured out but some have me baffled

The problems I have figured out so far:
*changed water pickup form the well pickup foot at the top of FT to the drain at bottom of FT so pump stays primed.
*The black hose was to soft and kinked so I turned the 12v 317gph pump upside down to avoid the kink
* duck weed bed leaks like a...... anyway I am just going to find some plastic/rubber liner for it later


The Problems that have me baffled and need so input on:

1) My end 4" gb pipe is 43.75" off ground at the low part of the drain and where it can flow over into the duckweed GB is 43" ....... should work but doesn't instead of flowing in the grow bed it fills the 4"gb pipe up and runs out the top

2) forgetting and bypassing #1 problem I disconnected the duckweed bed and the bottom 4" gb and turned the line back into my swirl tank turn the pump on and while running the water level in my grow beds was fine (need fine adjustment later) the swirl tank filled fast and swirled great I could see stuff going round and round , the water level should be 1/4 below the edge (I do have a lid I planning to cut a hole in the top to give me about 4" higher sides later) and the stand pipe is 1.5" diameter the feed pipe form GB is 3/4" or 0.75" BUT the water fills right over the top of the pipe and over the sides of the swirl tank:? at the same time water is flowing through the aerator pipe nipples back into the FT just not very strong pressure more of a drip probably because all the water is running over the side of the swirl tank

3) ok forgetting problems #1 & 2 for a minute , the next issue is after running the pump and turn it off I have a huge surge of water that runs out the top of my GB pipes/net baskets , there is no blockage, water levels where pretty good while pumping so I don't understand where this surge of water flow is coming form after the pump is turned off


Here are a couple system details that may or may not be helpfully:
* FT to pump feed line 3/4" ID
* pump to top grow bed feed line 3/4" ID
* pump to top GB head of water to be lifted is 5'6" or 66" form the ground (include pickup and head)
* pump is 12v Bocth automotive pump 317gph
* battery std 8d
* 90 degree elbows on GB are 3/4" ID
* GB pipes are 4" with 3.75" net baskets
*duckweed bed is wood sides with aluminum bottom (and soon rubber liner) the fill is a fill and drain fitting I got at the GZgrow hydroponics store and the drain is a 1" pvc

here are pictures of the fill and drain compression fittings and the aerator nipples I am using in my system

Your first problem is probably due to an air pocket causing a blockage in the tube going to the duckweed pond. I used to see this occasionally in loop siphons. Lifting the tube when you start to see backup might allow the water to push the bubble out but running the tubing different would be better.

Your second problem, the standpipe looks like it's too close to the top of the container. The rim isn't continuous on your container so some areas don't look to be 1/4 inch higher than the standpipe. Water has surface tension and I think it's overflowing the sides because the standpipe is too high. Once you fix this I think you'll get a stronger flow.

Third question I'm not sure about but I think it has to do with either water falling back to the pump and then blowing air and water back up into the pipes under pressure somehow OR a siphon that forms and breaks. Don't have a clue how either would cause this but since the water comes out in a rush these make the most sense to me.

Got any picks of the pump setup and feed to the pipes?

Well, I can't tell a lot about what's going on, but in one photo I spotted a major problem. The photo showing "[u]shows last gb pipe to duckweed bed witch is 3/4" drop[/one]" your drain hose is routed higher than the outlet and higher than the pipe with the grow pots. Water runs downhill. Reroute that one hose.

The green aerator fittings you show for aeration take a lot more water pressure to work than is probably being supplied by simple gravity, especially if the run from drain to aerator head is short or shallow, so all you'll probably ever get is a drip. Plus, doesn't take much to stop-up those spray openings. Simple, steady water movement at the surface does a good job of aerating water unless you are heavily stocked with fish.

Your swirl tank - I'd shorten the stand pipe to around 1" from the top ..... leaves a little fudge-factor.

Don't know exactly where you have placed your pump, but think "siphon". When the pump is running, water goes anywhere you route it. If the pump is lower than where you are pumping it, when you shut it off, the water in the lines wants to go somewhere .... usually back to where it came from. And since the line is "charged/primed", the water is smply siphoning back to where it came from, emptying anything it has filled until the water level gets low enough to break siphon. Make sense? Easy correction would be to place the delivery end high eough to be out of any water, so when the pump is turned off, the only water flowing back through the pump would be just the water in the line. Or you could go buy and install a check valve - a one-way valve .... making sure you notice the little arrows showing flow direction.

Hard to tell on the line in that pic, it looks like it stays below the pipe outlet to me but it could be an optical illusion. I'm looking at the grow bed pipe position in relation to the frame where the drainage line crosses.

scotty435
optical illusion is what is is , there isn't as much fall as i planed there but it still has 3/4" difference form where it comes out of the 90 on the Gb to the fitting in the bottom of the duckweed bed ........ in the picture I did remove the screen and just stood it beside the fitting so water should flow as soon as it pass the aluminum DWB bottom . Also the grey 90 degree elbow is higher then the black pipe going over the brace.
The 1/4" was form the rim I was not counting the band you see that holds the top down it was just a easy place to keep it so I didn't trip over it
I'll get you a picture of the pump in just a few minutes



Aufin,
those aerator nipples may stop up just don't know but I had them so I tried them..lol I tried removing one nipple and ran it both ways works but the nipples even a lower pressure seemed to make more water drops witch I think is better air if ever so small of amount..... if i had more pressure it would surly be better.

I can't really shorten the stand pipe it is cut level to the center of the aerator pipe that returns the water to the FT

Yall may be right I just run it and then put a cap in front of the fill line seems to help , it appears that it is siphon water up into the system after I shut the pump down until suction breaks ....... going to town to get a check valve in a little bit



here are some pictures of the pump scotty435 , one backed away , one close and one of the tag

Sounds like you're on the right track. It looks like it's probably a siphon issue.

My opinion, so take it for what it's worth, but since you asked ..... I think you've engineered your system with tolerances a bit too close. No room for adjustment. The fall of just 3/4" isn't much when you're moving water with gravity, especialy if you're going long distances. The black tube looks like it has valleys and rises which will inhibit smooth water flow. The water needs to flow without having to push the water ahead of it through the valleys, especially when it's going only slightly downhill such as what you pictured. If you can, channel the water with PVC pipe. You'll get a straight line without sags and such. You want the water to flow out as quick if not quicker than it enters the system. The swirl filter - you need to figure a way to shorten/lower the center pipe. Any hiccup and you're spiling your water. For aeration, any constant surface movement alows for the exchance of oxygen to the water. Doesn't have to be fast with bubbles, sprays and such, just water movement. You don't need mists, sprays, etc. If your pump is more than you need, if only by a little bit, put a T in the line to direct some of the excess water back into the tank to make the water move around.
Like I said, take it for what it's worth.

Aufin,
I aperpetiate your input I was not being argumentative I was just trying to explain the results with the nipples I had and not believing there the issue in the current problems and could see trashing them since they where already there until I tried them first. on the other water flow line I agree the tolerances are a bit too close originally there was supposed to be 1.5" fall at that point but 3/4" should still help to slow the water flow slow speed once it get to that GB at least was the hope.
The Tee off to reduce water flow and add more aeration back to FT with extra water flow is something I mite try this weekend.


scotty435,
I went to the store and go a check valve and some barbs and couple other fittings to plumb it , I'll will give it a try this weekend

Not a problem - didn't take it as being argumentative, just expanding on my thoughts as well. Trying to clarify the issues.

ok today's results have some improvements but still ave issues.

Here is what did today:
*change the last gb pipe to duckweed bed form that soft black hose to the harder clear hose and then it would hang under the support , it does flow better but I think I am going to shim that last GB pipe up 1/4" or 1/2" higher later
*I finally cut the hole in the swirl tank lid and put it in place witch adds a few inches to the sides
* I tried adding a coupler gaining about 2" height on the swirl tank drain, it gave more pressure at the FT aerators BUT it back flowed into the duckweed GB as it was set for original stand pipe height , Also the pump water flow was still to fast and raised water level quickly 5-6" above stand pipe before I shut it off!
* I added a Tee in the main feed line after the check valve and connected it to a ball valve that hooks to the other aerator pipe in my FT , I opened ball valve all the way and had good water flow out of both FT aerator pipes ........... BUT the Tee with ball valve all the way open was not enough to slow the water flow down enough that it would not over come the swirl tank stand pipe that should of reduced the water flow by 50% and it still is way to much ............I tough the pump was to small originally
* either the TEE or the Check valve did seem to fix the surge of water siphon after the pump shuts off

Ok, better explain the flow in your system, starting from the Fish Tank (diagram it if you can). I think removing the aerators on the lines into the fish tank would be a good idea. Back pressure from the aerators could be forcing the majority of the water to go into the pipes. What parts of the system drain into the swirl separator?

Sorry it took me a while, I had to draw it then it was to big and couldn't figure out how to shrink so I had to redraw


Water Flow:

FT to Pump , pump to check valve , check valve to top GB (#5) / tee to return ball valve
Gb 5 to 4 , Gb 4 to 3 , Gb 3 to 2, Gb 2 to 1
GB 1 to duck weed GB , duckweed Gb to swirl tank
Swirl tank to aerator pipes returning water to FT

OK, so this is what I would do, you'll have to decide if it's what you want or if something else might work better.

I would put a ball valve in to control the flow to the top pipe from the pump - it needs to be after where you split the flow to go to the fish tank. This will let you slow that flow down and send everything else to the fish tank for aeration. I would probably remove the aerators but you can try them if you like. I'd be a bit concerned about back pressure to the pump causing it to fail early but I'm not sure, if that's really a problem or not. Spray bars and venturis are other ways to aerate but aren't always necessary and probably reduce flow.

One thing I can't see is the water level in the Fish Tank vs the Water level in the Swirl filter. This may be part of the problem - are you worried that if you lower the swirl tank level by cutting the standpipe that the water won't drain to the Fish Tank correctly?