Backyard Aquaponics
A place to discuss aquaponics

Sorry, meant to add:

Sunlight shouldn't be a problem on west facing position in sunny QLD, but hard to judge from the drawing.

Not sure why you want to time your pumping precisely, if you are talking about timing it to the precise moment that a grow bed fills with water then this is not necessary. If you use auto siphons then
you can pump continuously. If you use standpipes then a timer is used but precise cut of is not required as the standpipe will act as an overflow.

If you use a sump then the rainwater overflow obviously needs to be in the sump.

Excuse my ignorance, but given the FT overflow needs to be higher than the GBs, how should I set it up? An obvious option is to drill a hole in the side of the tank, but I assume a siphon would be a better option? Still a bit confused on the whole overflow concept

Ryan, if you don't want to use a sump tank in your first system then the base of the GBs need to be above the high water mark in your FT.

Put the pump in the FT and have a gravity return - start off with 2 half barrels and add to the system...you can then monitor your water levels to make sure you haven't got too much GB space initially.

Once you have the experience with the smaller setup, you can then convert the rest of the backyard (plus the neighbours space) into Ryan's mega BYAP system


Fish tank overflow
Not sure anybody has ever installed one -unless it really buckets down and the system is exposed to the elements then not much water would be added...I thought you were going to put the system close to a wall, this would protect it from some of the rain

If the FT does start to overflow then use a bucket or rig some sort of cover to keep most of the rain away - vb is one person who has had his system uncovered for over a year and he hasn't reported inclement weather problems, think Steve's is out in the open too

re-reading, I think FF was referring to pumping water into the GBs and using a stand pipe for any excess to flow straight back into the FT before the pump cuts off - this means that the timer does not have to be precise

Hi and welcome! Right away I'm giving you bonus points in my book for wanting to do flood n drain. What type of grow beds were you planning on using?

How high is your deck? I don't favor putting the fish tank under anything that won't allow much head room for viewing/feeding/netting whatever. The back of my head is hurting just imagining the deck being only a foot over the top of your fish tank. I'm hoping the deck is really more like 8 feet off the ground. A couple questions, will the tank have a cover or some way to keep rain/dirt from the deck from washing into the tank? If it is treated wood, you don't really want the runoff going into your fish tank/food supply.

As to some of the other questions, Fish tank overflow either for heavy rain or for doing the CHIFT PIST idea. Yes it would require a hole either in the side of the tank at or below your intended high water level or a hole in the bottom of the tank. It can be dealt with either way but a hole in the bottom might be trickier to get at to deal with plumbing. What kind of tank will it be? any type of plastic would only require a hole saw to drill a hole for a bulkhead, uniseal, or tophat grommet fitting. If this is some other type of tank that you are having specially manufactured, you will want a drain hole some where and need to ask for it. Now there is something called a no holes overfow. There is a sticky thread in the Hardware section about them if you really don't want to deal with holes. There are some drawbacks to no holes overflows and if possible, a regular venturi drain through the side of the fish tank would probably be the better choice.

What kind of tank will it be? If galvanized, pleas be sure to have it lined/sealed with a potable water safe material.

Since you don't want your grow beds really high up, I would support the idea of a CHIFT PIST system (constant height in fish tank pump in sump tank.) Benefit of lowering the grow beds, single pump, pump in clean water, can't pump fish tank dry, water level stays constant for the fish etc. Only real drawback I see, you need a sump tank.

Sizing of sump tank. In general, go large on sump tanks. If you want to have the full 2:1 growbed to fish tank ratio, you almost need a sump tank as big as your fish tank. If you should go so big for this first system is really up to you. If you go with the more normal lower stocking density 1:1 ratio, you will want your sump to be at least half the size of your fish tank. This allows for the 40% water in the grow beds plus some extra for the pump, perhaps a top up valve and a little evaporation.

For the CHIFT PIST system, the grow beds need to be lower than your high water level in the fish tank and the sump tank needs to be below the grow beds for them to drain into it. in a CHIFT PIST system you can do the flood and drain of the grow beds either with a timer or with auto siphons. With either type of method, you should still install overflows in the grow beds so that if something goes wrong, they won't spill all your system water where you don't want it. If you go with timers or other ways of turning the pump on/off, know that float switches are not always reliable and you want to avoid ones not suitable for potable water systems. A timer with 15 minute increments should be good enough for most backyard AP pumping purposes. Lots of people manage with half hour increments. They do make fancy cycle timers that would be more precise, but they cost a lot.

So some of the terms you might need to research if you haven't already, include;
CHIFT PIST sometimes also called CLIFT PIST or SHIFT PIST or SLIFT PIST
Venturi drain
No holes overflow
auto siphons (perhaps even FLOUTs)

Good luck and welcome, would love some pictures of your planned site for your system!

Thanks for the replies everyone, especially TCLynx.

I've almost decided on going with a CHIFT PIST system. Having a sump doesn't bother me - for some reason I thought with a sump you would need 2 pumps. Provided I cans stick with one pump, I'm happy.

Now that I've ordered a 500L iron FT and 2 x 200L barrel GBs, I need to find a sump and pump - any recommendations? Would a large storage tub suffice?

Most of all, I need to work out my plumbing and pump requirements. I think the main thing I haven't got my head around is the siphon/overflow designs. I checked out TCLynx's thread here viewtopic.php?f=8&t=4086&p=147442&hilit=no+holes+overflow#p147442 , but still can't quite understand what I need.

Here goes:
To drain the GBs once full, I assume a standpipe and siphon is required. This will drain the GBs, then allow them to refill before draining them again. Whilst I understand the concept, I can't quite picture how to do this (particularly with barrrel GBs).

Then, the same process needs to happen with the sump. I assume a pump with float switches is the best option, by kicking in when the sump reaches the desired level, and stopping when its drains to the desired level. By pumping the water into the FT, once the water reaches the overflow it starts draining back into the GBs.

OR

The pump can run continuously, because the GBs drain quickly and immediately start refilling?

What I would really appreciate is if someone could draw a quick diagram (or point ti a thread with one) of how the above system would work.

Apologies for being a bit obtuse with this. I think I really need to get out in the back yard and play with a tub and hose to grasp the whole siphoning concept. I feel a bit embarrassed with my lack of ability to pick this up.

Thanks again for the help!

make sure the iron tanks are aqualined!!

have you had a look at my thread? There is a lot of pictures of standpipes I'll dig some up now....

Here you go, Inner standpipe, outer siphon pipe, crenelations in pipe to allow water into siphon.





how my 4 barrel system flow works:



and my dodgy 2 second drawing of a siphon:



hope this helps

Thanks - after a bit more reading, then looking at your setup, I know understand how those siphons work!

BTW, I envisaged cutting my barrels lengthwise, as opposed to the way you cut yours. What are the pros/cons of the different ways of cutting?

Pros: No supporting of the barrels reuired my way, deeper root area for tomatos etc.
Cons: Less surface are to plant on to.

probably some more of each, but I like not having to build frames to support them.

Hi Ryan

Don't ever feel embarrassed, you never know what you didn't know until you know it.

Keep looking at other systems, asking questions, and use the search on this site.

On the sump issue, any fish and human safe tub that will hold enough water to fill all grow beds and still leave enough water for the pump to operate will do. It is unlikely that all your grow beds will ever fill at exactly the same time, however you don't want the pump running dry. Be sure to anchor the tub into the ground so it doesn't pop out during heavy rain.

Some may disagree but for a pump I would suggest the following. If you pump continuously and use auto siphons on your grow beds you want to pump your entire tank capacity at least once every hour or so. You also want some excess pumping capacity that allows you to divert some flow directly back into the sump to create some aeration. For a system containing 500 odd litres of water any pump that will move between 1000 and 2000 litres an hour would do. Hey my small system is about that size and my pump will do nearly 6000 litres an hour, I just have more excess flow.

A timed system can use a bigger pump to flood the grow beds quickly then shut of to let them drain slowly using stand pipes (not auto siphons). Intervals of flood and drain are many and varied but 15 minutes of flood followed by 45 of drain is a good place to start.

Cutting barrels lengthwise provides a nice planting area for stuff but that is about the only really good benefit I can give. The cons include that the barrels need extra support to keep them from buckling out. And the biggest con in my book, the lengthwise barrel can prove a real monster to get the auto siphon and inflow rate properly balanced if you happen to choose the wrong size siphon to try and work with. The lengthwise half barrels work fine if you are going to run the pump on a timer.

I would not try to use a pump with a float switch for your situation in the sump. You will either want to use a timer or run the pump all the time. A float switch is for those people who have two pumps and need to empty the sump tank before it overflows because they have too small of a sump.

If you have a storage bin large enough to hold all the water you need plus some, it should do. Some things to keep in mind. Storage bins are often not meant to be out in the sun and could get brittle over time. They also sometimes arn't all that sturdy so you may need to give it some support so it doesn't bulge out and break. Make sure it is something you would feel safe drinking water out of since it will be in your food chain.

(I had to tinker with auto siphons a bit before I could really believe they worked too.)

i cut the barrels length ways way early in the piece...........never used them.........with i could "undo" and cut them OBO's way

VB's good with a plastic welder apparently

OK - I'm convinced to cut the barrels in half like OBO.

I will need to source a sump. Not sure what to use here, but will look at around the 200L mark.

Still not sure how to setup the overflow for the FT, without having to drill a hole in the side. Is this possible?

OBO - I noticed you used black poly pipe for some of your irrigation. Not sure if I should use that, or go with the white PVC pipe. Anything I need to know about?

I pick up my FT tomorrow or Friday, so I'm a bit excited about finally getting started!