Iron in Aquaponics - Part 2 (How much do I need?)
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- Опубликовано: 7 май 2013
- Read more: zipgrow.com/understanding-iro...
Part 2 - Calculating how much iron your system needs) - In this video, Dr. Nate Storey from Bright Agrotech gives you a simple formula to help you calculate how much iron your system needs.
Remember to ask other questions in the comments box!
Nate is the Co-Founder of Bright Agrotech, a leader in vertical, space saving aquaponics and hydroponics systems and a commercial producer in the high plains of Laramie, WY. With this innovative technology, Nate and the Bright Agrotech team feed dozens of restaurants, over 50 people in a CSA program and supply for a local grocer.
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I am 4 weeks into my aquaponic cycling and every question I had your videos have answered clearly and better than the DVD i was given. Cheers Mate
I have watched 100's of vids on hydroponics, aquaponics, aeroponics, and every type of method used to grow food but you are very interesting, informative, and useful. You are a real "Teacher", you have the ability to impart knowledge to others. that makes you a very valuable man, thank G*d for your talent.
No problem- thanks for the great question.
Hi Nate,
I have a dillema about your advice on Iron.
In your vid "Iron in Aquaponics" You said that 5 pound will last for 3 years and in this vid that You use it in a little bit lower rate but optimal for your system is 5oz per week.
So,my question is next: if 5 pound is 80 oz than 5 pound will be enough for 16 weeks(your system).
But 3 years is 156 weeks and if we divide 5lbs/80oz with 156 weeks than You actually use 0.51oz per week. And your math is 10x that. What did I get wrong?
Thanks!
You're welcome! We'll add it to the video to shoot list. Glad you found this helpful though.
Hi Brad,
This is an active area of academic research right now. Using plants to naturally (and inexpensively) chelate plant nutrients would be a huge benefit to the developing and developed regions of the world. My colleague Dr. Emmanuel Omondi here in Wyoming is doing some really cutting edge research in this area. With time, I anticipate that we'll have some excellent findings that we'll be able to apply to aquaponic systems.
Hey George, dosing with iron typically starts 3 weeks after the introduction of your first plants (around the same time you should start introducing your fish).
Good catch Daniel, let me clarify- we recently sized up our system, so we're on the Rakocy standard at the moment until we learn what our system wants. In our other greenhouse, we were dosing a much lower rates because we operated a system with a lot of volume at low stocking densities and low plant productivity. This means that our consumption was much much less and we brought our dosage down to the point that we were staying ahead of deficiency, but not wasting iron.
Hi Nate,
I am a huge fan and thank you so much for taking the time to help educate and demonstrate for us newbies. :) The Iron thing is baffling me. I am just starting but plan on building into something sustainable as a career. I currently have a 130 gallon raft system supporting 10 sweet basil. I'm dosing EDDHA at your recommended starting rate but my water has turned a rust red. The chelated iron is a black powder so I just assumed that's what happened. However it is difficult to monitor my fish (5, 7 inch Koi) as well as monitor my sediment collection. I built a swirl filter that seems to work well but not well enough. I keep getting sediment caking my roots. Sorry to ramble.. to the point; Is red water ok? and why do the basil leaves look dry? It's like the oil shine is missing. Not sure what could be causing that. I have the exact same seeds planted in dirt for comparison of growth, taste, texture, etc.
Thanks!!
Iron fluctuates widely in that range depending on plant uptake. I would recommend a range between 1 and 2 PPM typically. Most hydroponic solutions run iron at about 2 PPM.
Hi Rocket,
Lots of folks use blackstrap in hydro systems for organic iron, I've found its more messy than it's worth, and very difficult to measure/dose. That's why I prefer chelated iron, hydrated lime and epsom salts for all of my Fe, Ca, and Mg needs. . .
Dr. Storey. Your work is amazing! We appreciate the time you put into it (and I've definitely already subscribed!) You said we could adjust the amount of iron we use after starting at this recommended amount. Could you please elaborate on the indicators that would prompt you to use more or less as time goes on? Thanks in advance!
Dude this stuff is amazing. Thank you so much for doing this.
True,
Hi Nate...great info! I've got a 1000 gal pond with mostly koi in it and I recently added 4 IBC container halves to make an aquaponics system. It's working great but the plants were looking a bit chlorosed so I figured I would add some iron. The pH is about 7.5 so I bought some FeEDDHA (FERRIPLUS) and added 40g to the water and wow....that added a LOT of color! After a week now, the color has gone down some but it sure takes away from the beauty of the fish. Fish seem fine. Thoughts?
Thank you so much for taking the time to help
Of course, Wayne Lawler!
Really very good information...
i have question,
1.) After mixing 2ml /L what will be the PH for water?
2.) What is the ideal PH and PPM for the Aquaphonic system?
3.) All vegetable can use the same PH and PPM? or need to do separate system?
4.) Some vegetable need 6.5 and 7.00 how to control that PH and PPM
Hi Pirke, your math is right- I failed to explain that we'd just moved into our new setup. We do use less iron than I recommend, but we still are going through a couple ounces a week. I was remiss to mention that the 3 years our 5lbs had lasted us was on the 4000 gal system (with low plant production) system that we'd just moved from. Sorry about that! You're completely correct. Sorry to confuse you!
We're so glad you think so! Feel free to suggest other topics and we'll try to get any questions answered!
Hey there, Ace Hardware will either have FeDTPA on the shelves or they'll be able to at least order it in for you for pretty cheap.
I have just found your videos, and have only watched the ones on pH and iron, as I had searched due to issues currently with our system. GREAT videos, mahalo for all the help so far. Sooo.. . . . what about that iron PPM?
Hi Nate, all great stuff, keep it up. In part one, you briefly mention using plants to add iron. How about supplementing tilapia with Moringa Olifera. This plant has 25 times more iron than spinach, so I would have thought it was water soluble. Your thoughts please.
Hey Russ, check out your local Ace Hardware for a five pound bag of Miller chelated iron (FeDTPA) for about $50. Stay away from FeEDTA - It's super inefficient at pH's above 5.3. If you're putting in FeEDTA you're wasting about 90% of it. If you switch to FeDTPA or FeEDDHA you'll be using it more efficiently and saving yourself a lot of money in the long run. Hope that helps!
Struvite (basically Ferric Phosphate) is often associated with industrial/municipal wastewater treatment. When it forms in the wrong places, it can cause "scaling" (clogging of pipes by the precipitate), but operators often use iron to intentionally form struvite pellets (which can be sold as fertilizer at least for soil based agriculture) to remove that last bit of orthophosphate from the water stream before returning it to the environment.
I don't know to what extent microbes need iron, but I do know it is added to aquaponics water because it isn't really supplied by fish food at adequate levels for the plants (even though fish, unlike some invertebrates of interest, do have a hemoglobin based blood like ours, and thus need ferrous iron). I am wondering if an insoluble iron phosphate like struvite (as granules mixed in or as a surface deposit caked to the growth media, much as catalysts are sintered into high surface area carriers like zeolites in the chemical industry) could be mixed in the growth media of the plants to localize it where needed. In the water itself, iron could encourage algae and at high levels perhaps flavor the meat (I can taste iron in tap water, though I imagine the fish are selective in their uptake).
Continued. . . . We'll do the same thing in our current greenhouse- bring down the dosage over time. We'll find out where our consumption threshold is and then stay there to save money on iron. The 2mg/L rule is just a starting point. Many folks will bring it down a bit depending on the needs of their specific system. In our new greenhouse we will go through around 15 lbs per year.
Hi Nate, I've searched around here for FeDTPA and can't find anything so I've been stuck using FeEDTA. Do you have any brand names for the EDTA or places where it can be mail ordered? Thanks. -Rob T. PS good explanation on how to use Fe!
*How much iron do you need in your aquaponic system?*
Here's a video helping you to calculate the perfect amount:
Iron in Aquaponics Part 2 - How Much Iron Do You Need?
#aquaponics #science #fish #Aquaculture #growingfood #sustainableagriculture
I have spent months researching into home aquaponics and discovered an awesome resource at Keiths Ponics Site (check it out on google)
Bright Agrotech
very good! Thank you so much!
Thanks for reply - and thanks for the great videos and information.
Another good one. Like a supplier as well.
You explain the dosing for water quantity very well, thank you. But what I am asking is for monitoring. I have an iron test kit, but am wondering @ what ppm should I try to maintain my water. I think that if I dose continuously, without monitoring, I could be using too much or not enough. I have found some info that tells to maintain point25 PPM, up to 2-3 PPM. At what level do you try to maintain?
Sure, William, we'll add them to the list of videos to shoot! Do check out our Bringing Up pH video for more nutrient addition information.
Start dosing with iron at three weeks into cycling if you're adding other supplementary nutrients like kelp meal and continue dosing at 2 mg/l every three weeks. That will happen before you put the fish in your system. Hope that makes sense.
Nate, thanks for the video. I got your Key for Diagnosing deficiencies from your website, and this video (and video 1) gave me a lot of great information to go along with that Key. You did not mention how you add the iron. Sprinkle directly in the sump or? My system figured out to need about an ounce of FeDTPA (13%). I just mixed in in about a gallon of water and poured most of it in the sump and a little in the corner of my grow boxes. Hope I did ok on that. System seems to be responding well - Chlorotic issues almost gone after a week (weren't very bad to begin with). Thanks again. You're like my Aquaponics Prophet.
Bob
Hey bobsnrg thanks for that nice feedback! You can add your FeDTPA into your sump.
where i get a little lost is that the 2mg / l ratio i thought that was the dosing quantity to add every 3 weeks, But you then divided it by the 7% Chelate which brough it up to 108 mg / gallon. i have a 140 gallons systems and just added 1 g of 7% chelated iron the water turned yellow right away , i m wondering if i did add the 108mg/ gallons , the water would have turned dark yellow and also promote algae growth ?
Hi Nate, great video, very informative, thanks... question, you say 4000 gallon system, is that fish tank only or does that include the capacity in the sump tanks and grow media?
Hi +Matthew Young - That is for everything. Have a great weekend!
Dr.Nate, Thanks for your reply! I know anyone with a Ph.D is WAY smarter than I am... I have no problem with that 'cause I can learn... my question was, does the iron go in the water with/before the fish, does it need to circulate once around with the plants? AND... do you add that iron every 3 weeks or just once a year? Sorry, my ADD get's the best of me sometimes.
I'm still not informed enough yet to start the project but I'm working on understanding as much as possible first
Thank you!
Thank you
hello, thanks for the video it helps a lot, but i got a doubt in my kit test say that up to 0,5 mg/l in the water is very bad for fish, do your fish are okay? im starting a system and i need to put iron, int the water test is like 0,0 mg/l now i just got the EDDHA in a local store is like 6% iron. i m just worry about the fish. thanks
I have nettle tea for my soil garden (nettles brewed in water) which is high in iron. I’m assuming it’s not soluble otherwise everyone would be doing it. Is their anything I can do to make it usable for my small hobby system? 4000L
Same question applies to my comfrey brew which is high in potassium.
Dr.Nate, don't wanna'ask stupid questions but... here goes. Where does the iron water start... with the fish, after the fish before the fish ? I WILL start a sustainalbe system for me and some neighbors but first I gotta'figure out what the heck I'm doing here. Your vids seem to be the best ones but keep in mind... you da'Doctor... me? I'm a 58 yr.old piano player in New Orleans ! Thanks !! George
Hey Nate, I know this is a little off topic for this video but is the media in the zipgrow towers the only bio filtration you are using in your system or is there another bio filter in line somewhere?
Hi, like your video. Very informative. I've got a question. When you said you've got a 4000 gal. system, are you referring to the capacity of your fish tanks or the entire water circulating the system. Thanks in advance. :)
Hi, I was asking myself the same question. Did you fund the answer?
Cheers
Mahalo plenty for the kokua!! Will try to maintain that range!
Thank you!
Glad that it helped!
In USA measurements how many dry measures in spoons or cups would this equal. I'm too old to have the desire to learn metrics.Thank You.
Thanks very much though for the breakdown on kinds of irons, very helpful.
dry measures don't work because you need to calculate based on weight, not volume. Once you measure by weight once though, you can measure that volume of chelated iron and then add by a volume measurement from then on.
Are you going to follow up with additional videos for other nutrients? From what I've read, we might also need to add
- Potassium
- Magnesium
- Calcium
OK, I finally understand how to dose iron. Thank you.
Please help me out with magnesium.
Hi Dr. Storey, I start a very small aquaponic system about a month ago but the plants don't seem to be growing well. I dosed the system using fe eddha per the recommended dosage. My water become dark brown, near black in fact. Will this harm the fish and what else can I do to enhance the growth of the plants?
With regards from Malaysia
Hi Yin, Hmm. That's interesting. I've never heard of that happening before. If it's a relatively pure EDDHA, you should be ok. It shouldn't harm the fish. Regarding growth, it's very tough to tell without more details, like nitrate, light, ammonia, pH, etc.
I run my system pH from 6.0-6.4 and unfortunately have a bottle of Fe EDTA chelated liquid iron. I now plan on getting DTPA or EDDHA, but can I use what I have for the moment just to use it up? I just hate wasting money.
great video!
Thanks gregg stephens - Glad you found it useful!
before watching your video i thought all chelated iron was the same!!
gregg stephens Good thing you watched the video!
Vlad you said Fe EDTA was not safe. Some iron EDDHA or DTPA products come with EDTA chelated Manganese, and Zinc. Are these safe?
I have tested my water for total iron, but I don't know @ what ppm I should maintain. Do you have a recommendation? We have been on line since July 2012, 2,000 gl system, working our way up to 100 lbs of fish, about 800 holes.
Hi Nate!
As always great video!
What about iron sulphate? It's the only iron available for me, and I've been using it for two years now.
Is it safe?
Hey galkaenazul - Iron sulfate can be safe, but like everything the poison is in the dose. It's just not very effective in most aquaponics systems because the majority of the iron rapidly oxidizes. Iron sulfate is an inexpensive input, but what must be considered is the fact that a significant amount of the iron inputs never actually become available to the plant. Chelated iron products are much more expensive, but so bio-available that on a cost per unit of iron that they update, chelated iron is cost competitive with iron sulfate in these systems.
My system around 100 gallons. My calculator is need 5.0g. Right? Could I add Iron DTPA 11% to my compost tea?
Hi.Just sub'd.What about mollases in the system.It is high in iron,magnesium and calcium.Alot of organic soil growers use it to keep microbial colonies happy.Just a thought.
I'm trying to get the free e-book advertised on the video, "Top 10 Mistakes Made By Aquaponics Growers," and it isn't accessible. Is there a way you could send me a link?
You can measure the iron in the water?
The iron should be measured?
How many ounces every three weeks for a 550 gallon outdoor pool with 30 potted aquatic bulbs (Madagascar lace plants and cryptocorynes)?
Hello Dr. Nate, thanks for the info, very useful. I just have one question. Can I mix Iron and Epsom Salt in the same solution? Will going to have any lock out? Thank you
No problem. If you want to mix chelated iron and epsom salt it shouldn't be a problem.
Thank you Dr. :)
how can I get the free book of common mistakes? its a been a year of working with a system from 10 gallon fish tank and about to go to a 330 gallon ibc ib my 10 by 12 greenhouse....i have yellowing leaves and still need to find the things you talked about in this video. your videos are very helpfull thank you.Zach
Hey +Zach D - You can find our free mistakes ebook here: brightagrotech.leadpages.net/top-10-ebook/ - Sounds like you could also use our nutrient key, which can be found on our website (shop.brightagrotech.com). Glad you're finding the videos helpful, man!
Thank you for the info.
is adding too much iron really wasting money or just storing the Iron in the system? Does the Iron stay in the system and remain readily available for plant uptake or does it precipitate out somehow? I can see that if you are adding too much, it will continue to build up a massive surplus of iron over time unless it precipitates out.
Great video! Can You please give me the name of the person Dr...who invented the amount of iron as 2mg/l to use - thank You!
Thanks for the feedback. The other (and better) school of thought is to apply iron at the standard UVI system rate of 2mg/L every three weeks. (Dr. Rakocy at the University of the Virgin Islands was the first to design a standard DWC aquaponic system. Many of our aquaponic numbers and ratios today are drawn from his research.) For more details on how much iron to use, watch Iron in Aquaponics - Part 2 ruclips.net/video/qczagOJG5mI/видео.html
Thanks Nate! I found some Sequestrene 330 (NOT 138) on eBay last night and ordered it....probably a lifetime supply for 5 pounds! 10%...that may grow hair on your chest! ;-)
could I use eaf slag as grow media? it's almost 20% iron oxide but very very cheap.
+Rectal Tenesmus no idea, but if it’s relatively inert then probably. Best of luck.
Quick question, does the iron loose it's biological value over time? If a system had a very high water volume to grow bed ratio for thermal stability would the same UVI formula apply?
+Enigma Cipher Yes chelated iron can be broken down over time, and especially in systems with lots of exposure to UV light. The UVI formula is primarily for systems with the UVI water volume to plant number ratio, or lower. If you're going higher, you can still dose at that rate, and slowly reduce over time to figure out what your best dosing rate is, or you can do the calculations on the UVI system and reduce your dosage by the difference between the UVI ratio and yours. Great thought and worth bringing up!
I'm pretty sure theirs is all EDTA (I also notice a typo in my original question - the 2nd EDTA should be DTPA. ;-)
Hi Nate,
I have a aquaponic system made of concrete. It has been up and running for about 14 months. It takes a long time to grow anything in this system. Recently every thing is dying but fish are doing well. I have about 200 3-5 inch tilapia in the tank and about 300 mollies in the growing bed to eat the mosquito larvae The amonia is between 0 and .5, nitrites are 0. and nitrates are 2.0 My ph is 8.5 or higher by my test kit. I know that the concrete gives off a high concentration of ph but I would think by now it would have stopped leeching. I have changed water. I have tried ph lower, vinegar, and lemon juice. Nothing seems to help. Its the rainy season where we live and the water is being refreshed almost daily with rain water. I would think that water would have a nutral ph. Can you help me to understand what is happening?
Hey DaveCheryl Jereb , Nate says it might be two things.
1. You are under loading your system and its not producing enough nitrates.
2. Your PH is way too high and that might be caused by your system being made of concrete. Concrete usually contains large amounts of lime, which can inadvertently raise the PH of your water. A lot of AP growers using concrete like to line their systems with plastic or wax to avoid this.
Hope that helps!
Sorry, Wayne. Can't see your first question. Did you accidentally delete it to ask another?
Hey
So all these nutrients - (pottasium hydroxide, calcium carbonate, iron ,boron,sulphur) are they suitable for all the fish species (edible and non-edible).
Yes Sam, most of the nutrients are suitable for the fish, it just comes down to the concentration in the solution. Too much of any one nutrient can be harmful to the fish, similarly to how this applies to humans with any one substance in our water or air.
@@ZipGrowInc thanx mate 👍😊
@@ZipGrowInc or can I use a chelated micronutrient mix to deal with micronutrient deficiency ?
My system have 120 litter approximately. When I adding 1.5g (EDDHA-FE6), the water start turn red already. By calculation I need add until 4.0g. Should I stop or go ahead? is that my calculation correct (EDDHA-FE6 = 6% , 1g:30L)?
Ngieng H. H. Your calculation is correct, my system is 120 L , too. I added 0.5 g and the water turn red, which scared me. I chose to stop
I got some Fe EDDHA 6%. It says on the container that it is for ph 7 and above. Will it still be effective at ph's in the 6.5-7.0 range?
sure will!
+Bright Agrotech wow! must have a back log huh? lol.
You wouldn't believe us if we told you!
+Bright Agrotech well thanks. I still have my Aquaponics up and running. I don't need to supplement much anymore. thanks again.
hi nate i cant buy chelated iron fe eddha here in australia at all.. any help if there is another one i can use and cant get fe dtpa either thanks.. neil
Hi Neil Mcbride - That's not good! You might check with the good folks at growpacked.com - they might have some ideas. Best of luck.
Neil I found soluble chelated iron 13%, in BigW in a Melbourne store. Check your local BigW you'll probably find it there. Hope that helps.
When do we add chelated iron to a new Aquaponics system.
Hi Rudy, Some farmers only add chelated iron when they start to see deficiencies; we prefer to apply at a rate of 2 mg/L every three weeks preventatively . This is a suggestion from Dr Rakocy at the University of the Virgin Islands.
I just added 8 ounces of 3.25% iron from Ferti-lome Chelated Iron. I have a 2500 gallon system. I believe that I needed almost 20 ounces in there but opted to add less than half to start? Is 20 ounces the correct amount? according to what you were saying?
Thanks
Chuck
Yeah, you probably need more than that, but starting lower is ok. Better less than more. If you want help with the calculations, use this: able.ag/Calculators
Thanks Nate. THat is really helpful
Chuck
I would love to tour your place, Where is it located?
We're in Laramie, Wyoming! Give us a heads up if you're ever in the area!
HI Dr Nate I have a aquaponic micro system and i have problems with K and Fe. I have FeEDDHA product but it paints of red the water, its normal or not? Thanks have a nice day
Hi Oscar, there is red in Miller's FeEDDHA, but it won't hurt your system. Some people are bothered by it because they give tours or just don't like the look of it, but that's your call.
Hi thanks for your answer, I put about 50 gr for 500 gal, now my water is dark red. I worried about my fishes they are not eating well since I put the fertilizer. =( I hope they get better next days. Do you know if the red will disapear some day? Thanks
Hi Oscar, it will stick around for a week or two depending on how much you’ve added. If you really don’t want the red color, try the FeDTPA. The Miller's shouldn't be affecting appetite unless you added a LOT.
Thanks
Fish will be fine up to 2mg/l. Don't try to go above that number. Adding humic acid to your system will help reduce any toxicity if you're really concerned.
So, I read a healthy system will run a iron ppm of about 2.5 ppm to 3.0 ppm. Is that what you have in your system Nate?
Yep- in that range. Iron can range up to 5ppm or down close to zero with no bad effects, however you want the average to end up in the 2-3ppm range for aquaponic systems. For hydroponic systems I recommend closer to 5 ppm.
Cool man:) Thanks! I had Frogbit growing in one of my grow tanks and it was eating up my iron in like 5 days and I was dosing every 3 weeks. I would bring my iron up to 3.0 every 3 weeks and I had like 3 to 4 days of great growth then it seems my system would crash. A sponsor Hanna Instruments gave me a iron checker and now I can see what my iron is so that has been very helpful. Dude, I am good at gardening but it has been really hard to get a handle on the water. Right when I am thinking I nailed it something else goes wrong! Ha ha ha! Good for learning:)
Hello Nate. That amount of iron doesn´t harm your fish?
Nope. It won't bother your fish at all.
its sounds funny b ut would liquid chlorophyll do anything to help the plants? would it hurt the fish or anything else?I take it once a day for good health.
Hey +Zach D - That wouldn't help the plants too much, if at all!
ok just a thought, I looked last night and a strawberry plant I planted 1 week ago is flowering and its coming up green, could the colour difference be from changing from minnows to tilapia ? maybe before I got the new fish the system was too low on something else?
"Ace is the place"...only if we had one around here. ;-)
I wonder if anyone is actively trying to find a way to get micro-organisms to add Siderophores directly to aquaponics. Some way of stripping enhanced iron rich composts of all the nice good stuff in an organic liquid additive form. I think that would be awesome. Mother nature does it, why cant we..
Don't forget amazon for EDDHA
The question is, how do you measure iron deficiency?
i would like to know too
You can buy an inexpensive iron checker from Hanna Instruments.
fargobill well, nothing is cheap from them but I will check.
@@saeed6811 I think it was $50
15 oz every three weeks would be close to 16 lbs every year - in your last iron info video did you mean to say you go through 50 lbs in 3 years?
do iron supplements for humans work. I have a bottle.
2FYNFOYA - Probably best to stick to powdered chelated iron designed for plants. Humans take similar chelated iron, but we're not exactly sure what the chelating agents are. Better safe than sorry!
So roughly a pound every 3 weeks? That's about 17 lbs per year. How does a 5 pound bag last you 3 years?
+goltoof - You have to dose on a basis of your system volume. So without knowing what percentage iron you are using (6%?9%?13%?) and your system volume it’s impossible to determine how many mg/L.
I was speaking in reference to your system which you estimated at 4,000 gallons. In the previous video you claimed a 5 pound bag lasted 3 years. I'm probably missing something but the math doesn't add up.
+goltoof - no, it ends up being a few ounces every few weeks. The bag that I was probably referring to was for our system before we started dosing on schedule. Before that we dosed when we saw deficiency which was a really bad way to do it.
2mg/L Iron is too much in my opinion. excessive of iron would effect the fish grow; give false ORP reading indication to the water; additional Fe2+ would be oxidized to Fe3+ anyway. Adding less with more frequency is better. Our system is 0.3mg/L every week is enough.
Thanks for sharing with us. Great advice for our viewers!