Backyard Aquaponics
A place to discuss aquaponics

What are these bugs on the cabbages and broccoli? They look like sand grains and become bigger and more oval shaped? What Can I do to get rid of them in an AP system?

Aphids... Neem Oil

Just cover any exposed areas of gravel in the grow bed with newspaper a few sheets thick before spraying. Also cover FT and ST if spray drift can get into them. I've found that using the Neem at the rec rate that's on the bottle is a bit hit and miss, but using it at double the rate does the job. Sometimes, where the aphids are congregating, it gets a bit "woolly" for want of a better description, and the spray beads and runs off them, if so, add a few drops of soil wetta to the spray bottle.

You could also use Yates Natrasoap, it also works well, but if you get the slightest bit of it running down the stems of the plants into the GB, or spray drifting into the FT or ST, then your water will foam up for days.

Thankyou Mr Damage,
I looked up how the Neem oil works the net says it supresses their appetite so they starve - does that happen to the fish if they get a whiff of it too?

I don't know where you got that info from Pete, but I think someone may be confusing Neem and Dipel, which is a beneficial bacteria that gets into the gut of grubs and caterpillars and supresses their appetite.

Neem works by breaking down proteins in the insects exoskeletons and egg casings etc, causing them to soften and collapse in. If you get a thorough enough coverage Neem will kills insects within minutes, and even a light dose will see them die within a few hours or days.

I've sprayed it on a number of my systems and customers systems, many, many times without issue.

I have had a huge success with wood vinegar,I don't know if you can source it,but it's fish safe,beneficial to the plants and smells like you need to eat barbecue,it's very popular here in Thailand and I reckon I would be lost without it.

Do you need to cover the GB's before (I assume) spraying?

I never bothered when using wood vinegar,but I was never heavy handed with the spraying,the only thing wood vinegar wouldn't control was caterpillars,luckily they were never a big problem.

Thanks Guys I'll see what I can get.

Hey Yabbies, are you using real cold pressed neem oil or a ready to use mixture from hardware store?

If cold pressed, what is your mix ratio?

It's the Eco-Neem branded concentrate by Organic Crop Protectants (OCP) Gurkan. As far as I'm aware they are the only company in Aust with an APVMA licenced Neem concentrate, I may be wrong, there may be more now. It's also a registered organic product.

Their recommended application rate for aphids, mites etc is 2ml/Ltr from memory, but the bugs seem to laugh that off on occasions, so I now use it at 4-5ml per litre, that wipes the smile of their faces.

Thanks Yabbies, I have cold pressed neem oil and using it on my trees but never used on AP grow beds. I will try uisng your method and ratio and see what happens. Thanks.

That Neem Oil is as "dear as poison" funny enough. Got 1 - 100 ml container from Bunnings mixed 5ml per 1000ml of water covered the GB surface and used a hand bottle sprayer to dispense it. 12 hours later found a few more walking around so gave them a serve as well. Used about 500ml so far, it goes a long way.

I got rid of most of the aphids on the cabbages with the Neem Oil but found that when used on the Broccoli it caused the leaves to shrivel and die as though they got sun burnt. I need to do follow up mini sprays to get the ones that where hiding or arrived later.

Oh man I am sorry you have to deal with bugs and plants. Finding the proper ratio as well as which plants are sensitive to whatever we use can be frustrating. Over the two years I have had a greenhouse AP I've released around 20,000 lady bugs! They eat all the aphids and leave. I wish I could get them to reproduce as well as the aphids do, because this is getting costy. Good luck

Thanks Brian,
where did you buy the Ladybugs, how much$ and do they have any detrimental effect on the plants?
When I bought the Neem Oil there were heaps of other Pyrethrum based products on the shelves but I guessing its not good for AP systems as Mr Damage didn't recommend it?