Backyard Aquaponics
A place to discuss aquaponics

AP's described system would probably run fine on 4000 litres her hour (still turning over full system water every 1.25 hours). It is easy to get siphons to start - harder to stop them, so this flow rate will not be an issue for the siphons. AP is talking about going the whole hog and doing the 2:1 stocking density (based on the tank water anyway) so extra filtering and bio action may be important. Having said this - in the type of system proposed, it would be easy to increase the pumping rateas the density gets higher - because in all likelyhood it will not run at 2:1 all the time due to seasonal and harvesting fluctuations.

I have no arguement there F&F. I would not be going for anything but flood and drain. There are however different ways to do this and the specifics of each system and what the user is after will dictate what people choose. As stated earlier, using the hardware described and the figures given by AP - by using the classic design he would have a tank at 1/3 level (approx 25cm) on the flood cycle. Not suitable for the fix - but of course there are various solutions to cover this, including using the proposed 2300 litre sump as an addition to the 3000 litre tank to increase the amount of tank water and decrease the drop on flood cycle.

Th main discussion here is revolving around whether to use a siphon (with pump running continuously) or a standpipe (with pump on a timer). IMHO either way would work and each has its pros and cons.

OK, then I guess the easiest way to look at it is to give the autosiphons a go, while keeping a few bits of pipe and a timer handy as a fall back... but another issue is that if you have a couple of beds as floating raft to aid in the water volumes etc, how might you go about filtering them of solids? I guess you have to have them at a different levels to the other beds, fed and filtered from the gravel beds..... BUt.. with the siphons you will end up with a big rush of flow, not good for root systems suspended in water... Perhaps a small gravel pot before the raft beds...?

EB - you feed the DWC beds using a different pump that pumps from the sump. That way the water is already filtered. Raise the pump off the bottom of the sump to avoid pumping the sediment into the DWC.

Giving all my secrets away here . AP will have my proposed system at his place and I'll still have my crappy thing here. That way I can just go and visit him and can save the effort of doing it here

Yeah....... Leave your money on the fridge AP...

It's just not the same as having your own though VB..... Your just waiting to see what works best aint ya.... ?

Now but what about uses of the sump tank..... Thats a bloody big sump tank to waste and it would begood to see it be used for something... unless it's underneath other stuff, but then perhaps yabbies...... If you can keep all pumps off the ground then yabbies would be very do-able...

I'd have the main pump on the ground to make full use of water level - just protect it in some way from the creatures. Yabbs would be good because the fluctuating water level should not present a problem.

Potted plants are good, but take up water volume, so in a case like this, not so good....

I found out the other day that the ebara pumps I use have a plastic "skirt" you clip onto them around the inlet.. Minimum water depth is then 3mm....

Excellent. Might need me one of them for my big system (you know the one AP is building for me at his place). I don't suppose those suckers (excuse the pun) are continuous rated Joel??

Alright, we've got a holden and a toyota

Will all eight of the grow beds fill at exactly the same rate? I worried about the depth of water taken from my tank before I started pumping and how much water would be left once the 9000L of growbeds were full. But they don't fill at the same rate even if all the taps are fully open.

There will be some staggering of the fills.

What, no lada niva drivers?? My brother drives one..

I guess they will vary in their fill cycles a lot more if they are siphons rather than standpipes on timers J.......

Oh and no VB... Not rated.....

Man I miss out on these great conversations because you are there and I am here!

I own a Ford, a Toyota, and a Honda (motorcycle). Can I be in the club?

This is the wall I run up against every time with the gravity fed system...multibed distribution.


What will solve this problem entirely is an automated Y gate valve at the rearing tank drain. Grow bed plumbing branches off the Y gate valve to each cluster of grow beds (in this case 2 clusters of 4). The automated Y gate valve would need to be on the same timer as the pump, switching between the pump cycle. The pump runs for the alloted time it takes to fill one cluster of grow beds, is switched off, then the gate valve gets switched after 5 minutes (waiting for the water to finsh draining from the rearing tank). The timer then cycles the pump and gate valve every half hour and the other cluster of grow beds is watered.

Simple, but will require 1 automated Y gate valve and one digital timer.

This is a 12 volt or 24 volt AC flow valve that matches the size of my rearing tank drain pipe. This type of valve would be needed to channel water to different clusters of grow beds.

Mazda and Mitsubishi all the way!

How much MF?

Ok it is morning now and and I can think a little clearer. Having read through all the latest posts (Thanks everyone for your input) here is how I see it.

Fish tank 3000ltrs full, and gravity feeds to GBs. Sump 2300ltrs full, and has a submersable pump with float switch set at at 2 levels. 8 growbeds empty. GBs need approx 2000lts of water for flood and drain.

Cycle starts from sump.
Sump starts to pump water to full fish tank. Sump float switch turns off at predetermind level approx 300ltrs. Fishtank has a standpipe set up the same as VBs 1000ltr system. As the tank begins to fill from sump it goes over the standpipe and gravity feeds to the GBs. GBs have either standpipes or autosiphons not sure which yet. GB's fill and drain into sump. . Sump turns on at higher level approx 2300lts and starts the whole process again. This way the fish tanks always has 3000ltrs in it constantly. I think this is what you are talking about VB? is it right?.

AP

That valve ranges from $99 to $156 depending on the site you go to.

AP your understanding is spot on.