Backyard Aquaponics
A place to discuss aquaponics

Your dead right TC! Everyone system out there will differ from one to the next and nutrient and mineral lockout or uptake will be different from system to system.

Thank you for your thoughts on 'too much iron' .. not sure if its ever been discussed and Im unaware of over iron deficiencies or issues but Im sure there are in some shape or form. I suppose any heavy metal in large quantities is bad for fish. Dam I wish I paid more attention in chemistry...

Cheers.

X2 on that!

Thanks TC. Once I actually find some iron to add I will begin testing to find my iron levels. I'm going for commercial production as I already have a hydro farm I am selling stuff from. So I need the iron levels maintained pretty constantly to keep the plants beautiful for sale.

Still haven't decided between the maxi crop with iron or just chelated powder. Going to price out tomorrow.

Just picked up my iron. It's Agra sol iron 15. No idea how much to dose into the GBs. I've got close to 4500 gallons. So initially if imagine quite a bit. Suggestions anyone?

cmcguire99,
I was going to recommend you can get Sprint 330 iron from BWI or there is a liquid iron you can get through Gemplers. Ive used both and they seem to work and haven't killed any of my fish when used appropriately.

How much to add? Hum I would recommend getting the test kit so you can monitor what you are doing.
I don't know how concentrated or even what form this Agra sol iron 15 is so it is hard to recommend how much to use. In my big tower/raft system Ive used as much as 1/2 lb of the spring 330 or 4 cups of the Gemplers Iron for plants at one time. But a more normal dose was about 1/3rd of a lb of the sprint or 2 cups of the Gemplers. I need to get replacement re-agents for my test kit. I believe the pond plants were sucking huge amounts of iron out of my system water and when I took them offline from that big system I was actually able to maintain a higher iron level for several days without having to re-dose, and then I ran out of test re-agents and AES was closed for inventory so I didn't get to run the iron test yesterday.

I'm using the iron-rich waters of Trefriw Wells Spa located in the heart of the beautiful Snowdonia mountains in North Wales UK, shipped all the way to Australia. sounds posh? it is
I'm not kidding too
.
.

I scored a couple of boxes of Spatone (human iron supplement) just added a couple of sachets to my system today

Charlie- I wouldn't go above 4ppm iron for any length of time. Plants don't need it and the fish (species dependent) won't like it. I had someone dose iron for me when I was out of the office and they dosed in the sump instead of degas (straight to fish instead of straight to plant troughs for dilution). The fish were stressed for the rest of the day.

To the gent who asked why dose iron? Because it is not formulated into the fish feed in sufficient quantities for proper plant growth. This isn't up for debate, its been fact for years. You may say you never add iron? That's fine, you may be feeding more food per given plant area which gets you to the iron levels you need. The point is that out of all the nutrients, iron will be a big limiting factor and will be used up before many other nutrients start to limit plant growth so if you want maximum plant area for minimal feed input, you will need to dose.

I tested the iron levels in the water yesterday. 6 TBSP didnt even get me a reading. Its definitely going to take more. THe Agra Sol is 15% Chelated Iron. No other trace elements. I cant find the spirit 300 you are talking about. Could you give me a web address please?

Thanks Ryan.

Why we are on the subject and I suppose this question would rely on many factors.. but how quickly does iron get used up or depleted? I assume it is mostly taken up by the plants as opposed to evaporation and transpiration etc so are plants hungry for iron or does it hang around like salt?

Im just trying to understand the process after iron is added to a system I suppose. Im going to buy a test kit so I can experiment myself to better grasp the uptake and longevity of periodical doses.

Its a little frustration when doses are mentioned along the lines of "one heaped teaspoon" etc, its fairly ball park and not very reassuring.

My PH has always been mid to high 7's and its only now Im starting to experiment with the nutrient deficiencies and Id like to better understand.

Ok here we go. Correct me if my numbers are off.

the iron I purchased is 15% iron. I am shooting for a 2ppm level of iron in the system. My FT is 15 ft wide x 25 ft long x 4 ft deep. The FT is angled at a steady decline, so average of 2ft deep. I come up with a total of 5600 gallons of total water. Convert this to liters and you have 21198 L. SO....

2ppm=mg/21198L

42396 MG, now convert into pounds. .0935 lbs. the Iron I purchase is 15%.... So from these numbers the total iron I should add to the system is .623 lbs.

Please correct me if i am wrong about the way i came up with this number.

Thanks,

Chris

Anytime man. You are correct, it 100% depends on what you grow. It doesnt evaporate or leave through transpiration so yes, much like salt in that way.Ive had periods where it took 3 weeks to watch iron levels drop from 2.5mg/l to 1.5mg/l and then I've had intense grow outs where it drops every 7 days. Malabar spinach and Kangkong are HOGS! And I agree, with all the suggestions out there I rarely here about anyone testing to see what the actual levels are so it's nice to run your own tests and know you are where you should be for optimum growth.

What is the PH in your source water over there Charlie?

I'm a bit medicated right now but that math look dead on to me. I would go up to 2.5ppm (0.78lbs)though. Add it over a couple days initially b/c I've seen larges doses swing the PH up which would not be good if you had detectable ammonia.

http://www.seachem.com/Products/product ... hIron.html
I don't know how much merit this statement has since I'm not a chemist but looks interesting anyhow. From that link:


That's what I've always used with aquarium plants, pretty sure it's the same concept though. Either that or EDTA (dry ferts are always way more cost effective) .

Thanks Ryan. Thought the numbers were right. I added 2 oz 4 days ago. Will add another 4 oz tomorrow then hit it again in another three days.