Backyard Aquaponics
A place to discuss aquaponics

I use maxicrop %2 iron but I have also seen iron chelate in powder form which do yall think is better? And why?


And if you dont use these 2 what do you use and why?


No where on my maxicrop does it say organic does that mean its not organic? How bad is this stuff for humans?

I would NOT recommend drinking it. Seriously. My doctor said it was a dumb move.

Organic vs non-organic really means nothing. It's fish-safe and they breathe it. Good enough for me.

I've used a powdered chelated Iron supplement with good results (Sprint 330)
I've also used a liquid chelated iron from Gemplers but liquids are $$ to ship and I can get the powder semi locally.

The important thing with chelated iron supplements is you don't want the ones that have other metals in them since it is generally only the Iron we are lacking and other metals can build up to toxic levels for the fish if we are adding them in addition to what is in the fish feed.

Liquid Maxicrop is not certified organic because some step in the processing doesn't meet the "organic certification." That does not mean that the maxicrop is "unsafe" and to tell the truth, the kelp meals you can get that are acceptable for certified organic use would not necessarily be safe for heavy use in an aquaponics system since they still have too much nitrogen and could overload your bio-filter.

Just because something is listed for Organic use, does not mean it is "safe" for you or your fish. And just because something is not ORMI listed, does not necessarily mean it isn't safe, it just means it isn't listed for use for "certified Organic production." There are plenty of "organic pesticides" that could kill your fish and even be pretty bad for you, your pets, and beneficial insects. So, don't feel you have to be "organic" do a bit of research and check with others before dumping things into your system.

Now I've taken to using the maxicrop for spraying my plants rather than just dumping it into the water. That way my plants get more benefit from just a few ounces of the maxicrop rather than me having to dump quarts of it into the system.

I haven't been able to get maxicrop plus Iron locally so I've never used it and my source water is hard so I can rarely keep my pH down below 6.8 so the chelated iron products are beneficial.

I also use lots of molasses in my sprays. That also provides potassium, Iron and insect fighting properties.

Thanks TCLynx! exactly the answer i was looking for

I understand you use a iron test kit. what test kit does most people use? Any help would be nice. thanks jerry

I've got the same question.

I purchased an aquarium test from a local shop. Tests for iron in the water. What level should I be aiming for? I've got about 4500 gallons of water so chelated iron is probably the way to go.

Ive been using a laMotte test kit
http://www.aquaticeco.com/subcategories/2673/LaMotte-Test-Kits-Iron
That test kit only reads a Range: .05 to 1 ppm.
So I have to dilute the sample with distilled water to read the range I need.
I aim for a range of 2-2.5 ppm.

Now this is more testing and stuff than you are likely to need to mess with for just the average backyard system but if you are going for commercial production, if you wait for visible signs of deficiency to show up before doing anything about it, you are 3 weeks too late which is a big deal for crops that would only take 6 weeks under good conditions.

I believe there are test kits out there that read a range up to 10 ppm and that might be an easier test kit to use for the aquaponics but I would have to mail order that so getting the initial kit for a few dollars less doesn't save me anything when I have to pay for shipping. Aquatic Eco Systems is local for me so I can pick up the test kit and re-agents when out running other errands.

FYI, some systems are likely to maintain an Iron level longer than other systems. It will really depend on the plants being grown. The pond plants seemed to be sucking down a huge amount of Iron so I'm pulling most of them out of the big tower/raft commercial system to hook up with the quarantine system.

I've also noticed that my large media bed system has held it's Iron level with less dosing while the tower/raft system has been getting dosed far more often. The tower/raft system has lots more plants in it but I believe it's possible that the media bed system keeps more Iron available to the plants even when Iron levels are particularly low or the pH is a bit high.

Before when I was doing just media beds and backyard aquaponics. I would put a tablespoon of chelated iron powder in each grow bed (my grow beds were 100 gallons each) under the water inlet about once every 3 weeks. If experiencing a marked deficiency, I might say do the spoon full once per week or every few days till the deficiency starts going away and then back off to once every 3 or 4 weeks. Make darn sure you are actually looking at iron deficiency though since I wouldn't want you to over dose iron because of some other deficiency. Iron deficiency starts showing as new leaves growing in yellow but still with green veins. When you add enough Iron back in you should see the new leaves growing in green. In some plants the already affected leaves may not recover well but in other plants suffering from severe deficiency you should see the recovery move over the rest of the plant.
Yellowing of older leaves first is not iron deficiency.

How do you do the test by diluting with distilled water?

Ok so say I'm trying to get to 2 ppm.
Well the test kit only reads to 1 ppm.
So I usually use 1 part sample water and 3 parts distilled water for a total of 4 parts and I mix them. then I use that mix to run the test.
Then when I get the result I multiply the result by 4. So if the diluted sample reads 0.4 ppm and I multiply by 4 I get 1.6 ppm. If the diluted sample was 0.6 ppm and I multiply by 4 I get 2.4 ppm.

You can do this same thing with the nitrate tests to be able to read them. For that I often wind up doing 1 part sample water to 9 parts distilled water and then I multiply the result by 10 to know what the nitrates really are if they were up in the red which I generally can't tell what it is once the nitrate level gets to 40 ppm or higher.

Can you have too much iron TC? What effects would you see in this instance on fish and plants?

IronFish to go with IronMan lol

I ( and I emphasise this is JMHO) dont use iron or any other supplement for that matter . The reason I got into AP was because it was a simple matter (once you are cycled of course) of adding fish food only , the system then takes care of the rest .
But then again I dont do water testing or add air to my system .
But back to the question , why do folks add iron in the first place ?

Some systems have high pH, which will lockout the uptake of iron by your plants causing leaves to go yellow and plant health to decrease.

Yep, your right Lyndon.

My question remains please TC?

Too much iron shouldn't cause any other lock out s for plants as far as I know (which makes it a rare example)
But too much iron probably isn't good for fish so I would not want to grossly over dose Iron.

See the test kit that only tests to 1 ppm is from Aquatic Eco Systems which is primarily an aquaculture supply company so that tells me that most people are keeping the iron levels for aquaculture below 1 ppm.


And it is hard for me to agree with blanket statements that say you never need to add anything seeing as people are using different fish foods, different source water, different media, and growing different plants. Every one of these things will affect what nutrients are available in the water and they will affect if and what people might need to add to get what they want from the system.

Source water is a huge variable that can change drastically from location to location. Eve locations that that far apart. I just moved 17 miles and I was using well water at the old house too but the chemistry is different here than it was at the old house even in systems with inert media.