Backyard Aquaponics
A place to discuss aquaponics

I hate Mondays!

We had a nice weekend pottering in the garden; SWMBO didn't let me do any tinkering with the system or the plumbing, but we did plant out some new seedlings and shuffled some pots around in the pipes on Sunday. I removed the old temporary pond cover and replaced it with a double thick layer of UV90 shade cloth.

We have never taken into account of was the top-weight of the plants versus the securing configuration of the NFT pipes. My 3m lengths of 100mm PVC are just tied to the support stakes using gun-line; although this makes adjusting the levels of the pipes easy, there is nothing preventing the tubes from rotating. The three upper levels can rotate but due to their associated plumbing it is difficult for them to completely capsize; this is not the case for the lowest level. With 20/20 hindsight, of course it is obvious now.

Our spring-onions, leeks and celery have been going "gangbusters". They are huge and provided a formidable wall to protect the upper tubes from ground attack from the chickens! The plants were leafy, green and healthy. With a cold night and a heavy dew, at some time this morning the wet top-weight of these caused the bottom tube to capsize, rotating through 180 degrees. The pots tumbled out and the pipe was up-side-down and therefore cannot channel water back to the pond. Last week I switched off the aerator and left the pump to run its cycle 24/7. When I went to feed the fish this morning, the pond was completely empty except for maybe an inch of two of water. Ten of the trout were dead; two of the original stock and eight of the fingerlings more recently added. All the goldfish survived (they're bullet-proof!)

We immediately filled the pond with tap water, started the aerator and the pump to get some air into the system and get rid of as much of the chlorine as we can. I usually only keep a small bucket of aged water to top up the pond when needed, but I needed approx 500L this time. When I left to come to work, the water was still going in and some of the trout were still near the surface but gasping less. SWMBO will turn off the water when the pond is full again and leave the aerator running; the pump will resume its cycle. She will move the pots around and harvest some to reduce the load. I have some work to do tonight when I get home and dare say the balance in the system is going to be completely out for a little while.

OK... we've had a tragedy so what did we learn?

1) The submersible pump must sit on a plinth so that if an event which causes the pond to empty occurs again, the pond cannot completely empty. I know where the low-tide mark is and will set the pump suction just below this level.

1a) To avoid damage to an expensive pump, it might be prudent to install a level sensor so the pump cannot run dry. As my pump was a freebie, any cost to install a sensor and control system will exceed the cost of the pump.

2) The pipes must be secured so they cannot rotate and capsize.

On some more positive notes, whilst the pond was empty and we were clearing the casualties we took note of:

1) The covering of the pond means there is almost zero algae in the pond.

2) The skimmer system for the pump has been picking up the small solids from the bottom of the pond, only one or two stray leaves which made their way through the mesh and coverings were evident in the bottom of the pond. The filtering systems have been doing their jobs well.

3) The older fish were healthy and well sized. (Will provide photo when I get home tonight -- typing this from "work") They were just shy of 30cm and 300g. The new fish had shown tremendous growth since we purchased them, although the runt of the litter was among the casualties and had not grown much at all. The feeding regime has been pretty good, balancing the food intake with ammonia output and algae growth etc.


Although there were some positives, it's a bad way to start the week. Today might be the last day of this contract, so I could be out of work by the end of the day? But at least then I will have some more time to fix things up whilst I wait for some more work to come my way?



Scott

MAJOR HSM,
sorry for the losses. I'm happy you seem to be taking it in stride as lessons learned. Hopefully the chlorinated tap water doesn't mess things up too much but what can ya do.

Good luck with it. I understand how working gig by gig can be. I just had a 4 hour work call today, it was my only work since August 7th. Before that I only had one week of work in July. Yea, often gives lots of time for working around the house.

Bummer Scott... but good to see you've addressed the problem...

Thanks

I used to be in a job which spent a lot of time analyzing successes and failures in systems. If you don't learn why something works or doesn't work then you're more likely to repeat mistakes or waste time trying to reinvent wheels. I think it was Edison who said something like, "I haven't failed, I have discovered 10,000 things which don't work."

Here are the unfortunates, the larger fish are destined for dinner, the smaller ones will be composted:



Scott

Yes bummer scott, was a song about I don't like Mondays, hope you don't have a gun I would be devastated if happened to me.
But has been a lot of threads about shut off switches etc and must admit not something i've done, but another HSM on the forum might get me motivated, don't need 6000lts of water flooding the yard

Well, my first harvest happened sooner than planned. Like some others here, I have documented the progress:

Cleaning up:


Getting ready for dinner:


Ready for dinner:

Dinner:


All the food on the plate came form the dirt and AP gardens (except the avocado, our tree is in flower but it's too early for fruit).

Steamed Trout:
Two rainbow trout (cleaned and gilled)
1 Lemon, sliced
1 Lemon, juiced
Parsley, chopped
Fennel bulb, finely sliced
Spring onions, chopped
Butter
White wine
Salt and pepper

Wrapped in foil and baked in 180C oven for 20 minutes, served with fresh garden salad.

Bon apetite.


Scott

P.S. Yes, it was excellent!

Now there is a silver lining!!!! Or at least fish wrapped in foil
Glad it wasn't a complete loss.

Definitely, problems usually lead to more active learning. Often when things go well, people don't bother to analyze anything, it is only when they need to solve problems that they tend to pay enough attention and think hard about it.

Looked like a very fitting ceremonial dinner Scott.
Sorry for your losses.

Thanks Faye.

Can there be another silver lining?

SWMBO said tonight that perhaps we should look at improving the AP system (upsizing to an IBC-based system) before we complete the dirt beds re-design. Part of the reason might be the cost associated with the intended plans for the dirt garden; another part might have been noticing the fragility in our current configuration.

I probably wont get the large system as I want; our intentions (so far) are for a system quite similar to what Curly and Wavey installed with one IBC FT, sacrificing another IBC to make two grow beds and utilising the existing 500L pond as the sump. I will probably use pea-gravel for the medium and utilise a combined siphon/weep drain on the current pump and timer. I have a few ideas for the plumbing but will follow the basic CHIFT PIST ideal. It wont all happen in the short time-frame like the lads managed, ours (hopefully) will be achieved over a few weeks. I have to move some fruit trees and do some site-works, whilst trying to find a paying job too I guess we will have to wait and see what transpires?

Any recommendations/tips on how to upsize a system which already contains fish and plants?

I think I have a couple of options:
1) Install the FT first and fill it, then leave it to "rest" for three or four days with a small pump to keep the water moving. After the water has aged, cycle this with the existing 500L pond which houses the survivors from today's fiasco so essentially I will have a bit less than 1500L of water with the remaining trout and goldfish. This is where things are going to "interesting" as I will have to install infrastructure and plumbing to pump from the sump to the IBC whilst maintaining the supply to the existing NFT tubes and grow tubs (otherwise I'd have no filtration). There is going to be a D-Day which will involve the final rip down of the current system, removal of a juvenile apple tree to the site where the tubes are now, installation and plumbing of the new grow beds and replanting of the current plants.

or

2) Install the FT and the growbeds with a temporary sump and pump, then taking some of the water and the goldfish from the current setup, cycle the new system. When the cycling is complete (should be an accelerated process as it is not starting completely from scratch?) then I have a slightly-less-stressful D-Day to decommission the first system, transferring the trout and the plants from the old to the new.

I can see drawbacks and benefits from both methods. I guess I will have to come up with some sort of scoring/weighting scheme to determine the lesser of the two evils?

Hopefully, I can achieve this without killing anything else!




Scott

How far do things have to move? to make the new system?

Temporary plumbing to patch things together can make for a not so stressful D-Day if you have the spare bits on hand to manage it. I would probably go with the place and fill the IBC fish tank and bubble or pump the water for the several days you mentioned and then go about plumbing things together and transfer the fish to the new tank so long as it is still hooked up to the sump and flood and drain media bins, then you can work on moving everything else as you can. Then again, my system currently looks a real mess cause I keep trying out new things and there is all sorts of extra plumbing that is doing nothing currently that could be removed and re-cycled but I thought it would be handy to keep my options open etc.

Good luck in the planning/re-design

Just wondering if your 500L FT is going to be your sump and since you have sufficient space (from option 2) to setup your new fishtank and growbeds without ripping out your pipes, wouldn't you be able to get away with just another pump and staggering the pump cycles so that there is sufficient time for the water to drain back into the sump for the next system to be flooded??

So in reality you have two systems running but relying on 1 sump, hence giving you time to slowly transfer the stuff over.

Just to be safe, you may want to aerate the fish tank with airstones for a while and move the fishes into the new FT.

Sorry for not responding earlier...

I have made changes to system to prevent similar HSM:

To prevent the pipe capsizing, I just used an off cut of soft plastic hose laced with gun-line and constrictor knotted around the pipe very tightly. The friction of the hose and "stickiness" of the soft plastic prevents the tube from rotating. (Sorry the system didn't let me post the portrait view)


To prevent the pump from emptying the pond, I discovered I did not have any suitable plinth material that I would like to have in the pond, so I extended the pump suction and raised it to the level of low tide in the system. The only problem is that before the suction use to take up the fish poo lying on the bottom of the pond, now the fish poo is sucked up only when the fish frenzy they stir up the solids into the water mass where a smaller percentage is sucked into the pump and then filtered out, hence you can see specks of poo in the water column. (I suppose the fish stirring it up is better than it stagnating and becoming anaerobic?)


Just for interest: For those people who wonder about the benefits of covering water to keep the algae down, notice the lack of algae closest to the camera which is covered by shade-cloth compared to the end of the pond which still gets some middle of the day sun exposure.

Anyway... I am just about to go and purchase my IBC and commence the up-sizing. I have yet to decide on exactly how I am going to achieve it successfully, but I think it will involve a little from Column A, a little from Column B and some from Column C (thanks for the tips Ivansng). I will provide pics as things progress and hopefully get some feedback BEFORE I stuff something up!


Have a great day everyone!


Scott

Make the inlet pick up from the bottom, put an elbow in it to raise the suction pipe to the low tide mark, fit a breather at this point, then another elbow back down to the pump.

Pump will draw from the bottom of the tank (and a small amount from the breather) until the water level drops too low, then it will suck in air from the breather, stopping pumping, but not burning the pump out.

Ah yes... will give that a go tomorrow and see how that goes. That sounds like a plan!


Scott

(My dad was the engineer, I spent most of my life doing "other things")