Should I be feeding Iron and Phosphates seperately?

Hey everyone,

It just dawned on me, when I use to have a planted fish tank (this is how I learned about plants and nutrients, etc), people use to warn not to feed Iron (Micro nutrients) and phosphates (Macro Nutrient) at the same time (usually opposite days) because supposedly they would interact with one another (Iron would cancel out phosphates i think?). I tend to mix all my dry nutrients into a gallon container and feed. I wonder if maybe this would be causing me issue. Just wondering if anyone has any knowledge about this?

Thanks!

Xul said:

Hey everyone,

It just dawned on me, when I use to have a planted fish tank (this is how I learned about plants and nutrients, etc), people use to warn not to feed Iron (Micro nutrients) and phosphates (Macro Nutrient) at the same time (usually opposite days) because supposedly they would interact with one another (Iron would cancel out phosphates i think?). I tend to mix all my dry nutrients into a gallon container and feed. I wonder if maybe this would be causing me issue. Just wondering if anyone has any knowledge about this?

Thanks!

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Are you using city tap or well water? Both should have enough iron in that you won't have to worry about it. That being said, it's not a fail safe.

As far as mixing them, I dunno. I suppose you could do a normal feed and then a small dose with water a day after that.

Also depends on the medium lol.

You're fine as long as you aren't mixing the concentrated nutrients together. But you are just fine to add both of the concentrates to the same batch of water. Any good base fertilizer will have proper amounts of P and iron, some have to supplement with a Cal-Mag product (which typically contains iron), though I've found that in soil the issue is typically due more to PH being incorrect and the plant has no access to the iron in the soil/medium.

I use raw DNF (dutch nutrient formula) nutrients (kno3,k2so4,kh2po4,mgso4 in the form of epsom salts,trace elements, and plaster of paris "caso4") and use an aquarium calculator (the fertilator) to find my ppm per gallon. I'm sure most people buy the premixed nutrients as it's easier, but my way is much cheaper

Iron binds calcium.

hotrodharley said:

Iron binds calcium.

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So does that mean i shouldn't be mixing the 2? I generally mix all my nutes into the same batch of water.

Xul said:

So does that mean i shouldn't be mixing the 2? I generally mix all my nutes into the same batch of water.

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So do I and honestly I just read this reading about plant problems with LED lights. I don't know the answer to your question.

Xul said:

So does that mean i shouldn't be mixing the 2? I generally mix all my nutes into the same batch of water.

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I was under the impression that as long as both are being added to water and not just added together in their concentrated form, you are safe. Maybe I'm wrong, but I mix all my nutes up in standalone 5gal buckets and haven't had any problems yet.

hotrodharley said:

Iron binds calcium.

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I wonder why iron is included in many CalMag products then?

OldMedUser said:

I wonder why iron is included in many CalMag products then?

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And both in most Micros although supposedly GH no longer puts iron in theirs. No idea but I read about calcium issues using LED lights and how to mitigate them. That was included in the article.

I use Jungle Juice. Their Micros do have iron.

I guess that's what I love about my Floranova...one bottle, one dose of nutrients haha. But I'm a pretty simple/lazy grower and it suits me well. I rarely have to use Cal/Mag products so it must work decently.

Logan Burke said:

I guess that's what I love about my Floranova...one bottle, one dose of nutrients haha. But I'm a pretty simple/lazy grower and it suits me well. I rarely have to use Cal/Mag products so it must work decently.

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I doubt you could find a lazier grower than me my friend.

I began figuring out DWC in 2001 from references about water gardens the Mayan's used way back when. RubberMaid tubs with one 12" stone using AN 3-part. Still doing it but now the 3-part is pH Perfect so with DWC its a half hour, every three days to top up and tweak the nutes.

Growing in soilless now using the same nutes but will get back into DWC eventually.

Planning on growing out a few dozen plants of many strains and getting into making female seeds of mainly CBD rich strains. Have to make the precursor chemicals so I can make silver thiosulfate and rock some tran-sex ladies!

Xul said:

Hey everyone,

It just dawned on me, when I use to have a planted fish tank (this is how I learned about plants and nutrients, etc), people use to warn not to feed Iron (Micro nutrients) and phosphates (Macro Nutrient) at the same time (usually opposite days) because supposedly they would interact with one another (Iron would cancel out phosphates i think?). I tend to mix all my dry nutrients into a gallon container and feed. I wonder if maybe this would be causing me issue. Just wondering if anyone has any knowledge about this?

Thanks!

Click to expand...

Depending on what was in your fish tank, and how big it was, it may have required an unusually low ph, lower than what is used for cannabis, or most other plants, and in that case, it's safer to add iron and phosphorus separately, as due to the low ph (under 5), iron, will bond with phosphorus to form an insoluble compound, iron phosphate.

Blitz35 said:

Depending on what was in your fish tank, and how big it was, it may have required an unusually low ph, lower than what is used for cannabis, or most other plants, and in that case, it's safer to add iron and phosphorus separately, as due to the low ph (under 5), iron, will bond with phosphorus to form an insoluble compound, iron phosphate.

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Yeah i'm not sure to be honest, i never messed with PH, everything i read basically said you were better off buying fish to suit the ph you have than fight with ph, so that's what i did, and I found myself more interested in the plants than the fish themselves haha, loved the crazy aquascapes people could create!

OldMedUser said:

I doubt you could find a lazier grower than me my friend.

I began figuring out DWC in 2001 from references about water gardens the Mayan's used way back when. RubberMaid tubs with one 12" stone using AN 3-part. Still doing it but now the 3-part is pH Perfect so with DWC its a half hour, every three days to top up and tweak the nutes.

Growing in soilless now using the same nutes but will get back into DWC eventually.

Planning on growing out a few dozen plants of many strains and getting into making female seeds of mainly CBD rich strains. Have to make the precursor chemicals so I can make silver thiosulfate and rock some tran-sex ladies!

Click to expand...

Hahahaha does it not seem like, at least with DWC/hydroponics, being lazy actually seems to be a good approach? Just doing what needs to be done, and not tweaking with the environment every single time you're around your plants? Anyways, sounds like you've found your sweet spot! I had used AN two part PH perfect formula for my first DWC. It was likely my horrid growing skills, but I just had a lot of ph swings and ended up trying this single bottle Floranova and haven't tried AN again since. Now that I'm (slightly) more knowledgable, I would be interested in trying AN again!

I've been using AN for almost 20 years. Long before they brought in the pH Perfect stuff and I like the new stuff better.

My first try with pH perfect I got Sensi Grow. A&B, for veg and the Connoisseur Bloom A&B for flower. I've long had problems with very low RH that leads to easy nute burn at what is barely more than half strength. I figured it was from too much N and with the two part it's harder to limit N than with the 3-part so I bought gallon jugs of the 3 part a couple years ago and seem to be doing better.

The trick with the pH Perfect is to not even check your pH and use RO or distilled water. When you start messing with the pH it seems to go to shit. I've done whole DWC grows without once changing nutes so it's got to work but I did that with the older stuff as well. Did a lot of experiments over around 50 tubs worth of DWC since '01. I just top up and check ppm then add small amounts of nutes to bring the ppm up where I want it.

Al I use is the 3-part, Big Bud and Rhino Skin. Any old Calmag will do and I use little of that. Epsom salts in later flowering and I powder up some of my own supplements like zinc, iron, selenium, B-1 and ascorbic acid. I feed a half dose of BB and bloom nutes a week before flipping and give the other half at the flip as the plants feed heavy during the stretch then feed Lucas Formula style after the stretch. That seems to really help prevent nute burn, (toxic salts buildup), later in flower wheich was a problem before I clued into what was going on because of the lower RH. In winter it's hard to keep it over 30 and the plants drink a lot more then and take up more nutes than they can use so it gets stored in the leaves and turns them crispy.