Backyard Aquaponics
A place to discuss aquaponics

The high PH might be due to a "dead zone" some where,before you start adding acid it might be a good idea to have a look about in the pond & grow beds.
And check the KH,if that's reading 0,it's probably anaerobic conditions causing it.

What's the Nitrate reading?

We're new to this but our reading of the Nitrate levels in the previous photos looks acceptable. It's the PH that is off the chart and I blame the leaf matter at the bottom of the pond for that. Yesterday I made up a crude air-pump to hopefully suck the leaves and fish excrement from the bottom of the pond and into a mesh where I can rescue any unlucky fish.



The half bottle of PH-Down seems to have done the trick in the short term.



If I get the time today I'll be trying to suck up any sediment from the bottom of the pond.

The Nitrate might have something to do with the Phosphate levels.

If you have anaerobic conditions in the pond (the possible cause of the high PH),when you remove the dead leaves & everything else,that may cause the PH to drop very quick (not good) that's why it's not a good idea to add the acid yet.You can move the PH 0.3/0.4 a day for the fishes sake.

The plants aren't doing well probably because of the high PH.I missed that yesterday.

Hiya moneybox, next time you want to lower the pH you might like to use sulphuric acid instead of the pH down. Cheaper and beneficial for the fish.

Money, i love your trip to the city pic! I hope to take trips like that one day!

7341 might be on to something. It does seem like it is possible that anaerobic zones could cause the ph issue. I think i read something like that once or twice, oh yeah, it was on this forum.

I just started wondering about the cement construction of the pond. I know you sealed it well, but i wonder if it could somehow be getting through the coating and affecting the ph???

I've heard that some people throw a piece of cement in their tank to help keep ph from dropping. I thought about trying this, because my ph has been going down, down, and downer. It's actually been slowly brought up over the last few weeks. But, I still need to build a good buffer reserve.

So you were able to get a good look at the fish?

Thanks skeggley, I have a 4L bottle in the shed but Mrs M was reluctant to let me loose with it.

Will, we haven't seen all the fish at once due to the condition of the water but the ones that come into view are looking good. I pealed a handful of juicy green grubs off the spinach and tossed them in a few at a time. They were soon attacked by the fish so I took that as a good sign. It's a pity they ignore the pellets but they seem to be doing quite well on whatever nature provides. Mrs M removed the automatic fish feeder while I was away because it could have been aggravating the problem.

Ummmm my bad, meant hydrochloric acid... sorry mate put the sulphuric back in the shed...

What if you set a black soldier fly bucket with an exit pipe over the pond? It might give you a basically free food supply, with the same concept as the feeder, and they might be more palatable to the fish.

The black soldier fly like to breed in dark places, and the larvae grow there, then they seek out the light and climb , or crawl, out. So they would likely be falling into the water when the fish feed.

https://youtu.be/A5j4i8_7fHw

Something like this might work.

That sounds like a great idea and it's the type of food that they'd eat. I'd have to check that they are here in our environment. I'd hate to introduce another pest.

Just checked, they are available in Perth but I still need to know that we can introduce them to our area and if they are likely to survive and multiply.

The sunfish I have relish the larvae. The catfish have been skeptics.
I got lucky, and the Black Soldier Fly just showed up in my compost.

They have had a steady population for most of the year for about a year or maybe a little more.

They are attracted to compost for sure. If you keep a compost pile, you may have them in there already.

I would think that there are probably populations there if they are available anywhere in Austalia. The adults are quite big, and very capable of flying. They look kind of like a black wasp.

I'm not sure where they originate in the world, but I know they are in many parts of the world.

I'm not sure what the adults feed on either.

I agree with you though, about not wanting to introduce something to your area that isn't there already.

The larvae can be very plentiful if the adults find your box suitable for egg laying. If you keep them well fed, they will keep laying there. Mine just showed up in the compost, so I don't turn it as much, so they will keep doing their thing.

If you’re already composting or have a worm farm I’d wager there will already BSFL in it.
No need to buy them, give them the right conditions and they will come.
Here’s one of my AP hero’s thread, viewtopic.php?f=18&t=7224&start=1005&hilit=Francois , the last 2 pages, 68,69 on his thread is BSFL related and worth a look.

Francois feeds his BSFL better than I'm fed

I think we might see them at some point throughout the year but we have a lot of variation from season to season. A few weeks back we had small orange an black native bees buzzing about everywhere. The spangled perch were lined up by the overhanging plants plucking them off whenever they got close. Now there are hardly any insects about. Even the usual billion or so flies have deserted us.



I've been busy with new projects so since adding the PH Down I've not done much in the garden. Perhaps that's a good thing because things have turned around. The plants that have been stalled for months are suddenly sprouting new leaves and putting on a lot of new growth. The water is visibly much clearer too although it has a long way to go.

I'm really hoping to see the fish breed in the pond. Google tells me to expect many thousands of eggs to be laid in the reeds. We don't have any reeds in the water so I've created a synthetic nesting area using 1m long brushes bunched closely together. Hopefully that'll give the small fry some protection is we get that far



I lowered it into the water so that the brushes are just below the surface.

I was thinking of putting water chesnut in the tank for the little ones to hide in. Hopefully it will do two jobs at once. BSF are available from Future Green Solutions. You can Google them .You can get a kilo or a few tonnes of them. I am not having much luck with mine ,I will have to get some more. I am keen to see how you go, if they will eat BSF they may grow well. Maybe the reason that they don't grow very big is that there is always too many there and not enough food .There have been reports of one fish on a large pond and growing to 40 centimetres. Redfin are very stunted when there are too many in the pool .