Fish Safe Plant treatments

TCLynx

Well mealy bugs, I've heard of people wiping them off with alcohol swabs which should also work on other scale insects but it rather tedious.

Many of the soft bodied insects including aphids, white fly, scale insects and mealy bugs can also be controlled with SucraShield, you and anyone else around (including pets who's eyes are regularly open up in the air) when spraying should wear protective goggles since it can cause severe but temporary eye damage. Anyway, this stuff seems rather safe for aquatic animals and the main drawbacks I see with it are it's high cost and limited availability as well as the needing to wear protective eye wear when applying it.

As to meal worms, well the meal worms themselves make great fish, chicken and pet lizard food but keep in mind the adult beetles of the species eat plants. People who raise meal worms as pet food have taken up a sideline selling the Insect frass as fertilizer and pest control (apparently helps the plants produce an enzyme that helps protect them from plant eating insects.)

philnjp

Great thread guys - lots of good info.
Now question - where do the green caterpillars hide?!?! So far they are destroying the kale but little else - a few holes now appearing on bok choy. I do a daily check over the leaves and rarely find anything - yet each morning there are obvious large holes in the leaves. Occasionally I find little ones, and once a big one - but typically nothing.
Do they migrate down the stem into the media? Or am I just blind with green on green?

DrLuke

The caterpillars hide in plain site. The babies will be under the leaves, and almost too small to see when starting out. Otherwise if say its not caterpilla, and instead slugs/snails.

Slugs will hide elsewhere during the day and come to the plant at night. Try half oranges, beer traps, multigaurd, etc.

Marc d W

philnjp wrote:

Now question - where do the green caterpillars hide?!?! So far they are destroying the kale but little else - a few holes now appearing on bok choy. I do a daily check over the leaves and rarely find anything - yet each morning there are obvious large holes in the leaves. Occasionally I find little ones, and once a big one - but typically nothing.
Do they migrate down the stem into the media? Or am I just blind with green on green?

Hi philnip, if the frass (caterpillar poo) is large then it is probably a larvae of a cabbage butterfly (the big white butterflies you see around) or a cut worm or one of the caterpillars that live in the media and come out at night to feed. If there is no frass or it is very small it could be a early instar of one of the caterpillars I have just mentioned or a diamondback moth. The diamond back moth larvae tend to hang down on threads of silk if disturbed so give the plants a bang and see if you can find any. The diamond back moth larvae can also burrow in the leaves and so can be hard to find.

Apart from this +1 to everything Dr Luke said.

PS the cabbage butterfly caterpillars are probably hiding in plain sight so look harder or use the Force.

PSS the paper wasps you may see flying around your growbeds would be on the hunt for caterpillars. It is great fun watching them look all over the leaves of the plants (doing a far better job than I can) and then carrying off the unfortunate caterpillar to be butchered and taken back to the nest.

Here is some pictures I took last season of one butchering a caterpillar. (the things you see when you don't have your macro lens)

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Marc d W

TCLynx wrote:

Yes, be very careful with the spinosad since it doesn't actually require that much to be toxic to certain types of fish.

I agree TC but if used carefully it can, in my view, be used safely for some fish like trout. There are risks with many things we put in our tanks. Knowing and managing the risks is a prerequisite to so many things we do.

The LC50 (short term exposure) for spinosad is 30mg/l in trout but about 7 for blue gill. The degradation of spinosad in the aquatic environment occurs through a combination of routes, primarily photodegradation and microbial degradation to its natural components of carbon, hydrogen, oxygen and nitrogen. It is possible that some degradation may occur in the growbeds and this aspects deserves further investigation.

On the downside the long term toxicity over approx 80 days is 0.4mg/l. for trout

So what is the practical application of this. IMO if this is correct and we use it infrequently and carefully minimising any runoff it would appear that it could be used "safely" or at least safer than some of the other chemicals that have been used.

We can also monitor how much we use and if we assume say 50% runoff into the tanks we can work out the possible upper limit of the concentration of spinosad for our volume of water.

If the rate for use on ornamentals is 237ml per 100us gal (237ml per 380l) of product with an ai of 11.6% this equates to 0.6ml of product per 1l of spray. If the ai is 11.6% there is 0.072ml of ai in 1 litre of spray or approx 75mg of ai. Assuming 50% makes it into the fish tank water (IMO an unreasonably high amount) you would have, at a guess, approximately 0.0375ppm of ai in a 1000l tank from one 1litre application. So to get to a possibly dangerous level of 0.5ppm you would need to apply 10l of spray, ignoring all other factors such as breakdown in sunlight, degradation in the beds, removal via water changes etc. Also the product is rain fast after 6 hours.

So if used sparingly and carefully it could be used safely.

I think this is an important line of inquiry as many people get pest infestations in their system that they can’t control.

If we can find a pesticide that is relatively safe to use in aquaponics it will make life so much easier for us all and make aquaponics more accessible for the average punter.

I think it would be worthwhile if those that use this product report back on its success as a pesticide any possible problems that it may be causing the fish.

ps copper is highly toxic to fish, is not degraded in the tanks yet if used carefully and correctly has been an effective treatment for fish in the past.
pss I wish we had access to some of the more fish friendly chemicals you suggest but unfortunately we don't so we need to use what we have available to us, albeit with care.

TCLynx

Yea, I like having the wasps around to help with the caterpillar hunting but everyone else seems so afraid of them. Sigh.

As to the use of products, I'll let people make their own decisions but I'll still advise caution and care. (after having heard stories of people bringing the ingredients of a spray out to the system and setting the jugs on the grow bed and having an open jug knocked over to spill concentrated contents directly into the system while looking the other way and spraying with the diluted mix carefully........)

I prefer the products where there would only be a small amount of product used while the LC50 of the product is in the hundreds of mg/lt range so that even if there was an incident or minor disaster or complete misunderstanding of how to use the product, it might still not cause a problem.

But as noted, ya gotta use what is available.

Marc d W

+1 TC
Any chance you could slip us some of that AxaMax in the mail? Just kidding - the penalties are fairly steep for non registered chemical use here.

TCLynx

Keep watching for it Marc, or other products that are derived from neem oil. I wouldn't be surprised if it becomes available over there eventually.

So far the Bacillus Thurengensis products still seem most effective against the caterpillars for me and I primarily use the AzaMax for seedling treatment to try and avoid having things feed on the seedlings in the first place.

I think the Botaniguard, SucraShield or simply molasses/seaweed extract sprays and maybe worm tea sprays may be as good against the aphids when I had them last winter. (Well actually the aphids were a real problem because the ants were farming them and I couldn't really figure out anything that worked well enough against the ants.)

Marc d W

I will check with the National Registration Authority (APVMA - Aust Pesticide and veterinary medicines authority) and see if any of these products are under consideration for approval in Australia.

For ants I use a mixture of borax and honey to bait them and hopefully kill the colony. I buy 100ml bottles of the stuff premixed (Antex in Aust) and would go through 3 or 4 a season. It works well and I generally don't have a problem with our type of ants (stick nest ants - Iridomyrmex conifer, a predominantly nectar feeding ant)

rsevs3

TCLynx wrote:

As to the use of products, I'll let people make their own decisions but I'll still advise caution and care. (after having heard stories of people bringing the ingredients of a spray out to the system and setting the jugs on the grow bed and having an open jug knocked over to spill concentrated contents directly into the system while looking the other way and spraying with the diluted mix carefully........)

It seems very foolish to be mixing any chemicals over your grow beds... People amaze me sometimes....

TCLynx

COMMON sense Isn't.

justjoshin

TCLynx wrote:

Anyone know any fish safe ant repellent?

I'm not entirely sure that it is fish safe, but ground cinnamon is effective at repelling ants (I use it around my beehive sometimes). I would think it would be fish safe, but I haven't tried it so I can't guarantee it.

Charlie

Thats an interesting idea, JJ

mattyoga

They are not keen on peppermint oil either. I dowsed my air pump internals (not inside diaphragm though) with it after they made a nest in it and stopped it working. so far they have not moved back in. Will give the cinnamon a go next time.

TCLynx

I know I've tried sprinkling cinnamon around before and I have mint growing but ants here in FL are on the extreme side.

I've had people claim that growing mint there are no pests but I've had caterpillars attack mint before and seen ants on the mint so to me that means that one must just keep trying new things to find what works for the particular pests and situation.

(if you create a better mousetrap you are simply training better mice.)

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