Backyard Aquaponics
A place to discuss aquaponics

Well, after my first intro post here, I undertook a fairly extensive system re-design, and came up with a hopefully improved plan.

I'm going for a system in a polytunnel; I finally have a decent sized plot, with space to give this a try - and my philosophy is to try with the expectation of success; and what's the point of succeeding a little bit, right?

So, rather than try a small aquaponics set up, then see where it goes, I'm adopting the same philosophy as BroHay in New Mexico - "Go Big, or Go Home";Here's the rough layout;


http://i.imgur.com/TuNGtD3.png


My tunnel is going to be 14 feet wide and 30 feet long. I swap between metric and imperial units - the disadvantage of being in the UK, that made a half hearted transition to metric in the 70s, and didn't follow through.

At the moment, the site isn't level, and covered in junk; my friendly local Guy with a back hoe is going to fix that, probably in exchange for alcohol, probably this weekend. That's mainly how rural small village Scottish economy works; our official currency is the pound Sterling, but the actual currency is more of the "half bottle" variety.

My first post was asking about tanks - and I had real issues finding decent grow bed containers in the UK - either too small, or insanely expensive. I was struggling to find IBCs for sale as well - nobody would deliver empty ones, and hiring a self drive van for 1 or 2 IBCs seemed wasteful.

I got lucky, therefore, and found a guy selling ten of them for £35 each - £300 if I took the lot. I made an offer, and hired myself a long wheelbase high top Van - which took 3 IBCs at a time. Excellent! The only catch? The guy's factory unit was 80 miles away. So.. yeah, 160 Mile round trip.. 4 times. At least on the last trip I was able to use the spare space to haul the lumber that I need to make frames, doors for the tunnel etc.

The system will be a flood/drain CHIFT/PIST system, built out of these IBCs. Fish Tank Space is 2 full IBCs - 2000 Litres, interlinked with 4" Flanges/Short pipes. Another IBC is chopped and used as smaller tanks (also linked) for Fingerlings and quarantine if needed. I'm planning on fitting slide valves into the 4" pipes for max flexibility;


http://i.imgur.com/cpq6UIy.png

So, total Fish Tank space is between 2500 and 3000L, depending on the size of my "small" tanks, so I am planning for a Sump of 2100L. I'm sinking two full size IBCs into the ground as sumps, with a 110mm (4") pipe linking them across the central aisle of the tunnel.

My GB volume at day one will be about 3000 Litres, if it all takes off great, then I can swap one of my half IBC Fish tanks for a third full size one, and push it to 3500/4000 Litres... and possibly a third Sump.

But let's not get carried away, right?

I'm hoping to use two solid lift venturis - one in each IBC, each providing half of the water, each draining to it's own side of grow beds and sump - so although the system's all linked, it's also built as two of everything. I'm also expecting to use two pumps (so less CHOP, more CHTP... ) for the same reason - one in each sump.

I'm a BCP/DR guy to trade, so resilience thinking comes natural.

Outsanding decisions;

1) Whether to use Drain guttering or solid 4" pipe as the return drains under the IBCs. Thinking that falling from the end of the Bell siphons into an open gutter might add more aeration.

2) How much insulation to add to the Fish tank. I just completed a house refurb, and have been using big sheets of foil backed PIR. it's amazing stuff. My intention is to add enough insulation and heating to the system so that I don't freeze in the Winter. (it's -4 outside at the moment, and the worst it ever gets is about -9)

3) Whether to interlink the growbeds so that water flows between them as well as onto them; mostly thinking about a drain blockage, and avoiding flooding the tunnel... harder to flood the whole bed if each tunnel is linked to the one next to it. I have a ton of spare tank bulkhead connectors (was as cheap to get a box of 50 as it was to get the 4 I needed for another job...)

4) What size of pipe to plumb the gravity feed in. I am thinking 50mm (2 inch?).


So, what do you think? (apart from, of course, "more photos")

edit: Fixed Imgur links
edit2: PROPERLY fixed the imgur links... sorry!

Well, nobody responded to my questions, but let's be honest, I'm doing this for me, not for a pat on the back.

I pushed on anyway- first up was prepping the site, courtesy of a gravemaster JCB



I sunk two IBCs into the ground by about 1m, leaving the pallet in place (they are the plastic ones, so not worried about them rotting)



cut a decently large access hole into each - large enough for me to climb down inside and hook up the plumbing.



Sumps are linked together using 110mm drain pipe, with koi pond flanges to connect to the IBCs - these didn't look robust enough, so I cut a pair of circular washers from a sheet of neoprene to help with the seal, then applied a liberal amount of 'sticks like sh*t' clear sealant.



In order to fit the pipe, I used a rubber pipe soil pipe coupler with steel bands; my local groundworker tells me that they use these around here for all sorts of jointing of new pipe work onto traditional clay as well as plastic. should be okay - but I surrounded the pipework with gravel to make access a little easier if I need to get back into it.

Once that was in place, we filled around the IBCs, brought the site level, and ready for the growbeds and polytunnel frame.

I cut my IBCs into two sizes - all of the bases ended up two sections high;



Whilst the top sections were cut to either 2 sections or single sections. planning to use the 2x ones for flood/drain growbeds, and the 1x ones for floating raft.



Looking pretty good in place. main supports are medium density blocks, stacked to the right height, supporting a wooden frame built from 75x50 pine; the IBcs are drilled through the frame, and screwed into the wood with the Torx screws that hold the IBCs to the pallets.



for the sake of easier levelling, i put all of the IBC bases on one side, and the tops on the other.

Kept nice access to the sump as well



using 75mm timber made it easy to fit the return pipework. In the end I used 68mm circular drain pipe, with shoes pointed upwards to catch the siphons/overflows.



I remain unconvinced that the siphons are big enough - i used 21.5mm solvent weld throughout, and opted for simple U siphons rather than a Bell version.



the end of each siphon is a 21.5 ->40mm reducer. I fit a bit of filter mesh and a 40mm coupler ring onto those to hold it in place.



My fish tanks are interlinked with another bit of 110mm pipe, with a gate valve so I can isolate. Gravity feeds to the beds are plumbed in 50mm each way, with each side having it's own SLO. pipework is reduced down to 40mm at each growbed.

Steps from here;

I need to get the debris/fines/swarf out of this, so am running it with just water initially to pump all of the crud through to filter it out (blue barrels are a 60L swirl filter, and soon to be sand filter for this).



planning to run it with just water, then water + media, once it's clear of debris/fines, then see about priming the bacterial side of things.

I have a wrong sized pump that I got from ebay, so not too bothered about killing it pumping junk, then swap for the 'right' one once the system is clean.

In case anyone is feeling helpful, I am unsure whether to have the water drip into my growbeds straight from the pipe end, or bring it to a dripper bar - and then, not sure whether to drip above the media, or sink the dripper bar into the LECA...

Worth mentioning - my plan for the media is to have the 'always wet' section of each growbed pea gravel, and use LECA for the flood/drain area.

Welcome Theo, sorry I missed your original post back in November. I probably can't be much help as I'm just getting started myself so not a lot of hands on experience to answer your questions yet, but I am excited about what progress you've made so far and I'm going to tag along for the adventure!

So far looks like you've done a good job but I do have some suggestions.

Sand filters pretty fine particles and while it will work I think you'll be cleaning it pretty often. Have you considered using a Static Upflow Filter with floating media as a filter for the fines? You wouldn't filter quite as fine particles but I think this would be easier to clean and maintain. It would cost more initially (unless you're good at scrounging some sort of plastic media).

If you have a high water table and/or the soil along the sides of the sump stands any chance of collapsing you'll need to either keep the sumps full or put some bracing along the sides to help keep the bladder from collapsing inward.

You were asking about inflow and distribution grids in your November post. In case you haven't found the answer. Either with or without will work but with does improve the distribution of solids and nutrients through the bed. You do need to leave the grid and any other pipework within the bed unglued so that you can clean it out when needed. As far as above or below the surface - above . If you put it below, roots can grow back into the openings and block things up. If you use a distribution grid, make the openings point down so that they aren't exposed to light - this is to prevent a lot of algae growth. If you don't use a grid then you can expect to see algae growth at the inlet and a buildup of solids there as well, although, you'll be using an RFF so solids probably are not going to be a problem in your case. You'll still get plant roots growing back toward the inlet (tomatoes mainly). They'll grow toward the outlet as well so hopefully you've figured in some sort of media guard on the outlet that you can twist to cut them off.

If it were me I would ditch the siphons coming through the side and make a standpipe come through the bottom. You're going to need to prevent plant roots from getting to the siphon either way and having the media guard makes sense for this. It also gives you more versatility since it's easy to change standpipe heights and remove or add bell siphons.

Hope this helps.

Thanks for the good wishes Rob - hopefully I can learn some good stuff from the folks here and avoid some issues...

speaking of which - thanks for that Scotty.

I'm only expecting to use the sand filter to get rid of installation debris, and remove it from the loop when the system is up and running properly, but still - I think can get some good plastic media without too many issues.

You have confirmed my thoughts/fears about the bracing. when the system first cycled, I got some soil collapsing in as the bladder retreated - I'll head that one off at the pass just now. One of my neighbours suggested using large slates against the outer metal; I also have some left over outdoor rated ceramic tiles that would do the job nicely.

I hadn't considered aggressive root growth - that's another one to start considering!

T.

Glad to help Theo

Hi Theo,
Looking good, nice to see someone else from Argyll building a system.
I'm currently building a slightly smaller system inside a 10' x 12' greenhouse.
I've used a vermiculite/cement to build an insulating bund wall around my sump, it's the easiest cement I've ever mixed and easy to break away if required.

Have you found any good deals on LECA including delivery??

Cheers

Hi Mate,

Yup, it's a lovely part of the country - hoping to extend the growing season with this though!

good idea on the sump; I hadn't considered insulating it so much, but I guess it's on the surface, so won't be ketp steady by the soil...

I got my LECA from specialistaggregates.com - I'm not sure I would call it a good deal;

a pallet of 30x 50L bags set me back £300; on the plus side, they honoured the free shipping, rather than the usual Highlands and Islands rip off.

T.

Theo,

Great plan you are working towards , will be nice to see the end result.

Did you leave the valves in place when you connected the sumps together or did you remove the valves before connecting them?

Thanks Green Time,

yeah, it's coming along well; my LECA arrived this morning, just waiting for the gravel

I left the valves in place on the sump tanks, locked (they have a big phillips screw that stops the valve from opening) - these shulz IBCs looked pretty solid, and the valves seemed kinda integral to the bladder...

have you had instances of them failing/leaking?

T.

Thanks Green Time,

yeah, it's coming along well; my LECA arrived this morning, just waiting for the gravel

I left the valves in place on the sump tanks, locked (they have a big phillips screw that stops the valve from opening) - these shulz IBCs looked pretty solid, and the valves seemed kinda integral to the bladder...

have you had instances of them failing/leaking?

T.

Theo,

I partial-buried three ibc's for my sump. I also connected them via the 2" outlet and left the valves in place. Then filled over with gravel for easier access to dig back out later if I had too. After completion of the sump I was pressure washing 5 IBC's I am going to be using for fish tanks, while I was washing out the outlet I had the handle pop off on 2 of them. With the handle off, water freely flows out of the hole where the handle was installed. The handle appears to be pressure fit with a gasket. I was able to press the handle back in with a c-clamp; however, I have now lost all confidence in them even though it could have been a unique situation from the pressure washer at just the right angle to blow them off. I am now unscrewing the valves from the fishtanks and screwing on threaded caps (I am not using those valves anyway). I should have followed the suggestions from Rob-Ringer85 and David-dstjohn99 when they suggested to build a box for easier access should something occur and need quick access to the sump plumbing. Still debating on digging out the sump plumbing and pulling the valves off of those even though so far no leaks (it has only been a few weeks, though). If I do dig it back out, I will go ahead and make the access box as suggested.

I haven't had a problem with my IBC's leaking while in use, but I did have the handle of one pop off when I was draining my 200 IBC and moving fish in to the 330 IBC, but the previous owner had busted the tab off of the IBC that made it so the valve would only go one way, I'm not sure if that is part of the reason why the handle came off or not... but I reinstalled it and it's holding water again without a problem. Might be something to do with the pressure of the water holding it in the closed location but once the valve is opened the pressure isn't holding it so the handle pops off.... or might be something to do with the broken tab so the valve can turn farther than it should... idk... I guess long term I should probably do something as a reassurance that I don't come home to an empty fish tank... maybe just a rubber fernco connected to a cap seems how it sounds like the threading isn't standard so it's hard to find (from what I've read...haven't actually looked for parts).

Hi Rininger - i had a hassle finding them until I found the correct name for the thread on the IBC bottom valve;

It's an S60X6 fitting; I have changed a couple of mine so that they come straight onto my solvent welded pipework; there are two at the bottom for draining the fish tanks (if I have to)

T.

Hi Theo,

How you getting on with the build?
The weather in our area has been pretty awful for making progress outside, did you manage to get your poly tunnel up for protection?
I ended up ordering my leca from a company called woodland horticulture, £200 for 23x 45 litre bags, it's a good price per bag but £62 of that total is shipping cost to Argyll!!

Where did you find the best place locally for bulkhead/ tank connectors for your swirl filter?

All the best
Cheers
Jock.