Backyard Aquaponics
A place to discuss aquaponics

Hi everyone!,
My name is Will and I hail from Perth WA
I just purchased my first aquaponic setup in Dec last year and decided to experiment with a small project first to learn the pitfalls before taking on a larger setup. My tank is roughly 380 liters and i have 100litres of expanded clay in my growbed. I'm running a continuous flow system with a swirl filter. I have 6 silver perch (that seem very happy and have more than tripled in size) and 1 yabbie (other 3 died during a nasty heat wave ) My veggies seem like they are struggling though. I'm not sure if its the heat or pests. I have learned a lot from this forum so far and was wrapped when i realized it was west Australian! So i decided it was time to jump aboard and say hi.

I would love to pick your brains and ask you what seems to be causing this white discoloration to my almost all of my veggies?

and

That's a strange one Rhodesy... are you foliar feeding something??

Gday Rupert Thanks for the reply, I'm not foilar feeding anything

What's your pH? At certain pH levels many nutrients become physiologically unavailable to the plants. Spots "in" a leaf would make me think nutrient deficiency first. Normally white spots "on" a leaf would make me think powdery mildew - a common fungus that will spread very quickly in a closed high humidity and shaded environment (although I've had outbreaks on ornamentals in full sun at the height of summer as well - so I'm more inclined to blame the R/H). Fungicides and better fresh air exchange are the usual treatment, but I wouldn't try the fungicide with the fish anywhere near. Spots "on" the leaves is also often mineral build up from the foliar feeding already posited. Any tissue necrosis? Might want to snip a leaf and poke it under the scope for a closer look before doing anything if you've access to one.

White fly and lace bug larvae attach to the underside of leaves and suck sap from the tissue above causing whited out splotches pretty quickly, so check the leaves from the underside real closely as well. You can't see the white fly eggs without magnification, but they are very common in greenhouses, Yellow cards coated with stick'um set amid the plants will attract them but everything else I know of will require some sort of application that will likely end up in your beds.

If it's lace bugs the white splotches are usually followed by tiny little tar spots that are their excrement, so I'm guessing that is the least likely cause. Start with a tissue sample under a scope if you've the means. Best to know exactly where the board is before ya start throwing darts.

Thanks Galt, ill check the pH, I have done a closer inspection and found some small white flying bugs (white fly?) on the undersides of some of my leaves. Might try purchase some sticky cards like you say and see how that goes

Could also be fungus, there are many that are similar, like shot hole fungus.

I purchased some yellow sticky traps which have worked a treat! i think i had some white fly.. but my leaves are looking much better already! thanks

did you check your pH yet ?

Yes sorry for the delay in reply!, my pH is quite high looks to be around 8

I have brought a new pH test kit today and checked it 3 times with a result of around 6.3.

in the picture of parsley it looks like eggs, but i can be also be crystallized salts which can occure during hot days. rubb the parsley leaf with your finger and try if it tastes salty.

Cheers for the thought benstar, really hot days are over now and the cool change has hit, problem seems to have stopped on all the new foliage (since deploying yellow traps, applying eco rose, and squashing a lot of white fly) I checked my levels today, pH was 6.6 , Nitrate appears to be staying at 0 (really hard to mix the second reagent, hope im doing it right as it stays yellowish when i check it). My system is 3 months old now and im still struggling to produce fruit from my fruiting veggies. Is this relatively normal behavior? Im really happy with how quickly the veggies grow from seed in the system now though