Backyard Aquaponics
A place to discuss aquaponics

Hi All,
My system started off as a fish pond (see attached). But because of the location it's never been anything except an eyesore. It's had water and a couple of little fish but nothing much else.
I'd keep decorative fish but it's not in a good place for enjoying or I'd do simple fish culture but it's too small at just 500L.

So Aquaponics seems to be the best option!

As you can see from the pictures, the FT is high. I'm thinking of doing a CHIFT PIST system. Having the FT high should suit that method best.

I've guestimated the volume of the FT at 500L. So I'm looking at GB's of up to 1000L, an ST of 400+L and a pump rated at 500LPH. Is that basically correct?
What kind of fish stocking levels should I be aiming for to keep the system happy?

The previously installed outlet of the FT is small. Only about 3cm. I'm guessing that's too small but your advice would be welcome. If it's too small I'll have to either increase the hole size or (more likely) remove a brick from the top to create a 'U'. (The FT is brick clad with cement)

Does is matter that the outlet is at the water surface? Should it be at the bottom so that the solid waste is removed as well?

Looking at other posts I see that the gravel in the GB's will take up about 60% of the volume. That means when full, I'll have 600L of gravel with 400L of water (less a bit to keep it off the top.)

So does that mean it will take my 500LPH pump 48 mins to fill the GB's? But I thought I read that the pumps can be run for 15 mins every hour. That won't fill my GB's.
If I were to my pumps to run for 48 mins every two hours would that be a bit too long for my fish? How long does it take for your systems to drain the GB's? I understand that there should be a period of time between each flood where the roots and gravel are 'in air' rather than submerged.

What options are there for the ST? I may end up having to fashion a ST out of a couple of joined barrels (pipe joined at the bottom) Can I keep fingerlings in there? Would that affect water quality in the FT? If I set part of the ST at the ground can I get frogs and other wildlife in there? Again how would that affect FT water quality?

Oh, my there are so many things running around in my head and I have so many other questions!

I'm trying to get my head around the numbers and trying to imagine the system running. Please help me out...

Thanks
Paedur

Pretty much on the money Paedur... but your pump needs to move at least 500L/H at whatever head height you have...

And basically, you would probably be better off uprating to around a 2-3000L/H pump to ensure enough flow "head" wise... and for any further future expansion...


About 15 - 20 fish would be a good safe number to begin with...


Yep, it's too small... remmber that with a "Chift Pist" system... your flow to the growbeds is purely by overflow of the system... so pump size while important... isn't as important as outlet size...

i.e a bigger pump wouldn't be able to push more than the volume of water that the outflow could service... with potential overflow of the tank itself...

Generally, the overflow of the Chift Pist system consists of a riser pipe (slotted/driled) that extends to the bottom of the tank... with a "tee" piece at the top... and the supply to the grwobeds off the horizontal side of the "tee"...

This allows the solids to be "sucked" up the riser pipe.. and out the supply line to the growbeds...

Uprating your pump, and enlarging the outflow... will allow you to fill your beds with the normal 15/45 timer cycle...

Thanks for the quick reply!


I'd forgotten about the head. If I put the sump pump at or near ground level I'm looking at about 2m to the FT surface.
Are the pumps adjustable or restrictable? I know that by restricting the flow the pump may be damaged. It would be a bit sad to get an over-sized pump that overwhelms the outlet.




That's good info and makes a lot of sense. Is there any chance that I can put the riser over the top of the FT? That'd save me the manual labour of making a hole/slot in the side. I don't want to add a pump into the FT. Just in case of failures and the extra energy consumption.

One thing I need to learn about is siphons. They are a bit of a mystery to me. Perhaps there is a siphon based option here? Although from what little I know about such things they seem to be rather fiddly. Not like a bit of manual labour to make a small hole bigger. Not a lot to go wrong with a hole!?

Paedur

Sure... lots of people using aquariums do so....

Search for "no holes overflow"....

Thanks for the pointer to no holes overflow. I'll look into that option.

Thanks again

You could use an air lift pipe to pump water over the edge of the F/T to a grow bed then use bell syphons to a sump then a pump back to the F/T with a float valve system in the F/T to stop any overflow , you would need a pressure controlled pump though.

Hey Paedur, welcome to the addiction

You can read up on auto siphons here on the forum, on the new aquaponic WIKI or look for affnan's blog on the web, all give give you great info on them. I personally prefer the auto siphon/constant pumping setup as I feel its more reliable than an electronic timer.

CHIFT/PIST does seem to be the way to go, read up on something called a 'Solids lifting overflow' or SLO, will probably have to drill in a bigger hole into your concrete for that but I feel it will be more than worth the effort in the long run. Mind that you must make sure that the fish can not get into the SLO or any other overflow/pipe you have in the FT, I've lost a number of fish to this and am still struggling against it.

Try to get your hands on one big GB rather than a number of small ones, its not complicated to split up the flow but is much better to keep it simple and have as few pipes as possible, easier construction and easier maintenence. Try to use quick release pipes or that screw on thing that lets you take them apart.

Test EVERYTHING BEFORE you put in the gravel and the fish for leaks and accessability, its no good if you can't easily reach all the tanks, GB's and piping.

Have a check on the gravel you're using, make sure it isn't limestone or marble as this will buffer your pH too high for the plants, an easy DIY test is putting some vinegar onto your gravel, if it bubbles then the gravel is no good, you can do some reading on possible grow media right here on the forum. Whatever you do use remember to wash your gravel, you're creating a closed ecosystem so must monitor what goes into it.

Get your hands on an aquarium water test kit that tests for pH, ammonia, nitrite and nitrate, this is essential or you'll be flying blind, not a good thing at all.

Also read up on fishless cycling, its the much preferred and efficient manner to start up your system.

You must shade your FT and ST, protect them from direct sunlight, easy to do by just throwing a tarp over them, if they get sunlight then you'll have algae growth which will eat up the dissolved oxygen and kill your fish.

Get some airstones and an air pump, again standard aquarium supply, to oxygenate your air for the fish, also putting in an aquarium filter won't hurt.

A backup power supply for the whole system, or at least for the air pump in the FT, is a good idea.

Theres a plethora of people here with a lot more knowledge than me and we're all rooting for you, so good luck and tally ho!

Erina George, could you further explain that? Is it the same as the inverted 'J' tubes. I'm tending towards making either a hole in the side or a slot in the top of the FT as this is simple and foolproof.

Abdul, Thanks for your good information. A lot of good tips there. Did you manage to get your gravel sorted out?

For the system I'm thinking of either a traditional flood & drain with a stand pipe. This I would prefer to do with a float switch to turn off/on the pump rather than a timer for better reliability.
Or a continuous flow pump coupled with either a looped siphon (simpler) or a bell siphon (a bit more complicated)

The SLO is a good tip and it answers a question I've had. I guess a grille over the entrance would prevent fish from getting in. The size of the grille would depend on the fish size you have. Too small a grille and it may get clogged with debris. Too large and the fish would still get caught.

I have the space for one large GB but sourcing it would be a problem Also I have no vehicle access to my home so everything has to go on a little hand cart and pushed up my hill. I think I will have to use a couple of smaller GB's. Depending on what I can source I'm guessing on 2-4.

You are right about the community here. I only started posting here today and already I feel more confident in what I want!

Paedur

Yea I did get it sorted out, sort of, the gravel I had was limestone/marble so went out and bought river rock, cost me about about six dollars for a bag which was approx. 40 kilos, got two bags and was goot for three GB's with a combined volume of about 70 liters...

A bell siphon isn't that complicated, just a standpipe with another pipe, the bell, over it. Check out affnan's blog he has videos and diagrams and everything, much more reliable than an electronic timer and the looped siphon, though am not sure about the looped siphon, haven't used/built one of those.

I would forget timers and float switches and go for continuous flow with an auto syphon of some sort. Simpler, and that is always good.

Agreed. A continuous flow with an auto-siphon seems the best way to go.
The actual syphon type can be decided later. Basically its either a bell or a loop. In some ways I think it depends on the form of my GB. Some will be easier to handle a siphon type than others.

I'm not familiar with the pump operation. My FT is 500L so I need a pump capable of 500L/h at 2m head. And I've seen advice to get a bigger pump than needed to allow for friction loss, manufacturer claims loss, and future upgrades.
Are the pumps adjustable? If I get a big pump can I 'turn it down'?
If I do a continuous flow system I should aim for a slow(er) fill. I'm worried that a too big a pump will effectively keep the GB's flooded all the time.

Too what extent will restricting outflow from the pump introduce back pressure which can damage the pump?

Paedur

With a bigger pump you simply put a T piece in your delivery hose with a valve. This points back into your fish tank. By opening and closing the valve you can regulate how much water is delivered to your GB with the excess giving aeration to your FT.

That's so simple! Although for me the excess flow would be directed back into the ST as I'm doing a CHIFT PIST system. It can still perform aeration though as the water is pumped back into the FT eventually.

Although... ... perhaps I could have another smaller fishtank up on my patio for decorative fish... hmmm hmmm.

Can you hear the cogs working?

Hi All,
I have activity to report for my AP system!

First - some shopping:
got 3 big blue barrels (130L each) for just HK$30 each. These are for the ST.
got a Quite One 4000 pump
Got my water test kits. Ammonia & Nitrite. Don't need a nitrate cos' there won't be any left after my plants use it all up. (being optimistic here)



Setup changes:
The GB's will no longer be below the FT. Rather they are promoted to a place on the patio which is ABOVE the FT. I'll be making the GB stand out of slotted angles.
.

A crossroads:
I can either continue to setup with the ST and pump from the ST into the GB's which will return to the FT.
OR
I can do away with the ST and use a spider/aquaponics/sequencing valve to fill the GB's individually (or in pairs or in threesomes) directly from the FT. My GB's are little boxes (total 110L cap.) so the drop in water level won't be too great (500L FT dropping by about 150L if I fill 3 GB's)

Both have some pros & cons although the AP valve option does seem better.
I'm a bit stuck on the implementation though. I have to interrupt the flow to allow the valve to switch to the next outlet. Well how do I do that?
Using a timer is fine, but the mechanical timers have a minimum of 15min segments. With a 15 on, 15 off, 15 on, 15 off it will take me 2 hours to complete the sequence. During the summer days (30+C) I'd worry about the GB's getting too dry. I'm not too convinced about the reliability and cost of electronic timers.
Any suggestions please!

The ST option is fine except I'd prefer not to have to make all the plumbing etc for 6-8 GB's. Plumbing the GB outlets is a must. Do I have to do all the inlets as well?
Maybe I'm just lazy...

Your thoughts & comments welcome and most needed!!

Thanks,
Paedur

OK,
A day of proper work. Not a lot to show for it though - I can't beleive how long it took me to put the two GB stands together.

ANyway here,s a pic to show my efforts.

The plastic boxes are my GBs. I've got eight of them. On the right of the pic is a length of 100mm piping I found on the side of the road. I reckon I can chop it up and use it for the standpipe.

One problem I have is that the stand's are too long. The GBs will fit no problem but the space I planned for them to go is too small. So they will have to be sticking out and blocking access to part of my soil GB. Oh dear.

Next job is sorting through some wood I have for the 'tabletops' and varnishing them.
Then plumbing, media delivery, media washing... then a nice cuppa tea!