Backyard Aquaponics
A place to discuss aquaponics

Where to buy and what to buy for fertilizer and additives and what should be avoided, dosing of the product would be nice as well per 100 L? Preferably in Melbourne.

What currently use
kH up: Potassium Bicarbonate(only found eco fungicide in liquid form)i used any others?

gH: Magnesium Sulphate ( Epsom salt), Calcium carbonate

Iron: seasol (has too much N & P)

Trace:?

Others:?

Would prefer solid form as its cheaper.Any other things I would need to add to a system?
Doesn't seem to be a central post for this

Pretty much the only thing I add is chelated iron. Plants yellow, and I'll add some, it comes good in a week and a bit. I usually just get it from bunnings.

Every now and again, I'll add some seasol powerfeed, it'll bring up any trace elements, but I don't do it that often, every two months of so. Seems to work well. Charlie carp will do the same also, but be careful how much you put in.

I don't have to worry about bringing up my ph, I've got a bit of limestone in my gravel, so it keeps it on the low 7's without me doing anything. But others add brickies lime (from bunnings), and calcium carbonate, they'll mix it together (do a search for the quantities, I don't need to do it, so I can't remember the amounts), and add it when needed.

What is the pH of your system ? What is your media ?
How many fish. and what deficiencies are you experiencing.
what fish food you are using and how often (FF is a primary system input)
what are your current ammonia & nitrates ?
The problem is that what works for one system wont necessarily work for another.

It also depends on what you are trying to grow and what season it is.


eg. I use sulphate potash as sold at Bunnings etc, Iron Chelate, Seasol and occasional Seasol power feed.
In winter or if nitrates low I also use a *little bit* of dynamic lifter and Blood&Bone Plus direct on grow bed.
and just do some regular water can with FT water every few days (rain washes in anyway).

your issue may be that you already have some things based on what you are using.


I apply via watering can direct to grow beds at recommended doses or diluted foliar spray.
But do it much less frequently than an earth garden (maybe every couple weeks depending on what growing)
Then dose is less of an issue - just use the watering can rates or less.

on Seasol - Seasol is recommended because it has potassium and is LOW in N or P - see bottom.
(plus a few other things). Seasol Power Feed is a different story as it has N&P.

If you have enough nitrates in AP then you are mainly looking at potassium and iron.
(then maybe magnesium and boron etc)


If you want solid form inputs (soluble) then one option is to look at foliar feeding.
or watering can onto the grow bed with a watering can (followed by a watering in with just water).
But many soluble mixed have Urea (which converts to ammonia).


there are some trace element mixtures in solid form BUT they contain copper and zinc which are not good for fish. I use one in garden but not AP - have wondered how it might go but not 100% sure - you get copper and zinc in powerfeed etc anyway (I guess the amount is very small and just enough for plants).

Hi Colum,


I'm assembling what I need to build my first flood and drain media bed of 1m x 2m x 30cm. I vinegar tested 3 or 4
types of gravel I can source locally, and a white crushed 3/4" gravel reacted pretty well to my vinegar test. I'd descibe
it as being similar to the bubbling a bit of Coca-Cola that has been sitting out for a few hours might do. I've been
toying with mixing a bit of the alkalic gravel in with the neutral to offset the natural pH slide of an established growbed.
Did you mix in the bit of limestone in your gravel or did it just come on its own? I haven't read about anyone trying
to pre-mix in alkalic gravel to fight the downward trend of pH. My plan is to mix in maybe 5% white alkalic gravel
with neutral gravel in a 600L growbed and see how that goes. I suppose that same idea might also work for a bit of
iron in the mix...

--
Sam

I would suggest not adding anything to your neutra gravel. If you want to try the alkaline stuff, put it in a mesh bag. That way, it's easily removable if it's not what you want or you could try a couple different things and use what works best.

ahh that's good to know that Seasol is low in N or P, so its good for trace/iron, apparently EDTA form of Chelated iron is toxic/not really good for AP systems so looked for other forms https://www.youtube.com/watch?v=E4_hCAnymFw, video explaining iron and had this saved in my bookmarks http://www.greenfingers.com.au/store/?fertilisers,22 which sells Iron chelates EDDHA, any other known source google search wasn't that helpful.

Had abit of look around in bunnings, they had Garden Lime/Dolomite Lime for Calcium carbonate but wasn't sure how pure it is i can source from http://aquagreen.com.au/catalog.html but bunnings would be alot cheaper depending on its purity which I couldn't work out>_<. But Potassium Bicarbonate(Eco-fungicide) is alot cheaper to order from aquagreen @ $14.50 per 1 Kg than bunnings.

A couple of the products you are looking for are available through my online store:

(a). High quality European manufactured EDDHA Chelated Iron 9.5% (nearly 50% more available Iron than the one you linked to)... $14.50 for 200gm:

http://perthaquaponics.com.au/EDDHA

(b). Pure Potassium bicarbonate, no surfactants (Eco-fungicide contains 6% surfactants which are basically detergents)... 1kg for $19.90:

http://perthaquaponics.com.au/Potassium_bicarbonate

http://www.duralite.com.au/hobby-growers/
They can help you out for DTPA , EDDHA is probably a "better" product but will turn your water so red you can't see your fish
viewtopic.php?f=1&t=26128

I sourced both iron & potassium carbonate from an ag store (CRT) had to buy a 20kg bag of pot. but at $4/kg was cheap enough & iron dtpa (7%) at about $30/kg but I had to buy 5kg....shared out with a couple of others worked out pretty good...

EDDHA is absolutely a better product. Haifa are one of the world's largest manufacturers and suppliers of high quality plant nutrition products and they only rate DTPA to a pH of 6.5, whereas they rate EDDHA to a pH of 14... here is a quote direct from their website:
Here is the link: http://www.haifa-group.com/about_haifa/company_profile/

As far as EDDHA Chelated Iron turning your water so red you can't see your fish, or even so you can't do reagent type water tests due water discolouration... THIS IS SIMPLY NOT TRUE!!!... It may be true if you add Iron to your system at the rate Nate Storey suggests in his videos, which is simply not required IMO. At the tiny rate actually required to fix Iron Chlorosis and maintain a healthy system, water discolouration definitely isn't an issue.

In the last couple of weeks I've had three customers asking if I sold DTPA because they didn't want EDDHA due to the two supposed issues I just mentioned. So two days ago I ran an experiment for one of them.

I've had Iron Chlorosis start to show up in plants in the shop IBC display a couple of times in the past and I've rectified it in a matter of days with the addition of only a ¼ teaspoon of EDDHA Iron into 500L of water. So on Monday when I ran the test I used that rate and added a ¼ teaspoon into the system, allowed it to circulate for about 10-15 minutes, then took pics of the water in the FT, in test tubes, and looking down through a 250ml cup of the water... You couldn't even tell that I'd added any Iron.

So I then took it a step further and added another ¼ teaspoon, making the amount added to the 500L the same as the widely recommended 1x level teaspoon per 1000L rate we used to see on forums, allowed it to circulate for about 10-15 minutes, then took a second round of photos.

In the second round of photos there is still definitely no hint of discolouration in the water when looking at it in a test tube. In regards to looking down through the column of water in the 250ml cup, which will always give a better indication of water colour, both myself and the customer came to the conclusion that there was a very, very slight, almost undetectable, pinkish tinge to the water, but considering it couldn't be seen in the test tube sample, it certainly was not enough to affect a reagent test, and definitely wasn’t enough to stop you seeing your fish.

Due to the forum limits for pics I have included them in three lots. The first and second lots are of the water after adding a ¼ teaspoon into the 500L (½ level teaspoon per 1000L), and at this rate it definitely resolves Iron Chlorosis issues within a matter of days. The third lot of pics are after the second ¼ teaspoon was added to the same 500L, making the amount in the system the same as the widely recommended 1x level teaspoon per 1000L.

Iron Chlorosis is such an easy deficiency to diagnose, it can usually be diagnosed very early and can be rectified so quickly, I don't see the need to maintain ridiculous levels in your system. I haven't had to rectify an Iron issue for quite some time now, because I add pinch (and I mean only a pinch) into my 500L system about every 4-6 weeks and I haven't had an Iron issue since.

Draw your own conclusions from the pics below:

Water after adding first ¼ teaspoon to 500L...

Water after adding a second ¼ teaspoon of EDDHA Iron to 500L, giving a rate the same as the widely recommended 1x level teaspoon per 1000L...

Mr Damage, what is the recommended watering can dilution rate for the Iron (ie. per 9-10L) ?.

probably case that if applied directly to the grow beds with a watering can it would make even less difference and be directly available for the plants.

Thats great Yabbies, the brand you are selling seems terrific, but to say, "As far as EDDHA Chelated Iron turning your water so red you can't see your fish, or even so you can't do reagent type water tests due water discolouration... THIS IS SIMPLY NOT TRUE!!!... " I think there is plenty on this forum to say otherwise...perhaps we need to be brand specific on these discussion...although I do agree usage seems exxesive....

I suspect it has very little, if anything to do with brand... up until about 3 months ago I sold a different brand, with the same result in regards to water discolouration, or lack of it.

It has everything to do with dosage, as you suggested... IMO those saying it has turned their water so red they can't see their fish, are putting way too much in. When 1/2 a level teaspoon per 1000L will fix Iron Chlorosis and not discolour your water, why would you add more?... I thought most AP'ers wanted to avoid, or at least keep additives to a minimum... It is possible to over do it, excess Iron can cause health issues for the fish and plants.

Water colour aside, the issue that's been swept aside here is the availability of the Iron at different pH levels...

Most people looking for chelated Iron are doing so because they have Iron lock out due to high water pH above 7.5, with most new systems in WA starting out with a pH in the range of about 8.0-8.5, what use would DTPA Iron be when it's rated to a maximum pH level of 6.5?

ahhh thanx for that Mr damage dosage rates is always welcome wouldn't want to turn my tank red lol. A 1/4-1/2 dose seems little so thats good too, how often would you dose that or just when the problem shows up?