I keep running into this problem

[Bill.de.Cat]

No clue about sterilization, though recently they have been getting hell about forever chemicals. Yeah, had issues when using RO, but I was also using FFOF for soil

I use FFHF ( milder than OF) and have a 3 stage filter out at my well and a 5 stage RO filter under my sink, I use Mega Crop 1 part ( the old stuff) with .5 gram epsom ( per MoG's recomendation) and I usually do fine...any problems are usually due to pH in the auto pot res. so I only mix 2 days worth at a time.... the less that's in there, the easier it is figuring out what's wrong.

 

[MotaZona]

I don’t see any aeration in your mix.

 

[tronN00dles]

I get rust spots like that when I use too much calcium, typically in the form of too much lime in conjunction with hard tap water.

I see you’re adding lime. Do you know the ppm/EC of your tap water? If it’s high to start, it in conjunction with the added lime could be a recipe for locking out P/K.

On the other hand, too little calcium can also cause rust spots so there’s that lol. But between the manure, lime and tap water, I’d lean toward more to excess causing lockouts rather than a deficiency.

 

[DogterB]

I get rust spots like that when I use too much calcium, typically in the form of too much lime in conjunction with hard tap water.

I see you’re adding lime. Do you know the ppm/EC of your tap water? If it’s high to start, it in conjunction with the added lime could be a recipe for locking out P/K.

On the other hand, too little calcium can also cause rust spots so there’s that lol. But between the manure, lime and tap water, I’d lean toward more to excess causing lockouts rather than a deficiency.

Ooooh, maybe! Yeah I'm using a soil recipe from a well respected grower and from talking to them, they are thinking along the same lines. I don't know much of anything about our city water. I looked up the water quality report awhile back but couldn't make heads or tails of it. I don't have an EC/PPM meter or anything, so I can't really test. I've been thinking like you, with all that is in there that there is little chance of deficiency. Here's what I could find about my water:

 

[Talonxracer]

From that report the treated water Ph is rather high at 9.49, that can certainly cause issues!

 

[N/A-Greengo]

From that report the treated water Ph is rather high at 9.49, that can certainly cause issues!

PH 6.0 - 6.5 is best. Also, you can safely use 7 drops per gallon of Tetra Aqua Safe plus to clear your water of any Chlorine, chloramine, and heavy metal contaminates. Do this while aerating for at least one half hour. Then adjust PH accordingly.

 

[DogterB]

From that report the treated water Ph is rather high at 9.49, that can certainly cause issues!

PH 6.0 - 6.5 is best. Also, you can safely use 7 drops per gallon of Tetra Aqua Safe plus to clear your water of any Chlorine, chloramine, and heavy metal contaminates. Do this while aerating for at least one half hour. Then adjust PH accordingly.

Oh wow, I didn't even see that! Weird, because when I've pH'd the water after sitting out a day or so it says ~7 pH, but that is using drops to check pH as I don't have a pH meter. I think I'll try pH'ing the water to 6.5 before it sits, then check it again and adjust before putting it in the res.

I'm also curious of the great @Mañ'O'Green 's opinion on all of this

 

[Mañ'O'Green]

PH 6.0 - 6.5 is best. Also, you can safely use 7 drops per gallon of Tetra Aqua Safe plus to clear your water of any Chlorine, chloramine, and heavy metal contaminates. Do this while aerating for at least one half hour. Then adjust PH accordingly.

STOP. Do not use Tetra Aqua Safe in your nutrients or grow. It will bind to and remove all of the critical trace minerals needed by the plant.

Iron, Zinc, Copper, Selenium etc....................

Oh wow, I didn't even see that! Weird, because when I've pH'd the water after sitting out a day or so it says ~7 pH, but that is using drops to check pH as I don't have a pH meter. I think I'll try pH'ing the water to 6.5 before it sits, then check it again and adjust before putting it in the res.

I'm also curious of the great @Mañ'O'Green 's opinion on all of this

Water absorbs carbon from the air this binds to calcium carbonate and it drops out of solution when exposed to air over time. This will change the PH of the water. RO water will grab a bunch of carbon when first exposed to air and can drop from~7PH to 4.5 in short order.

I aerate my water at least overnight with an air stone/pump before I use it. Mix the nutrients PH to the desired level. Then fertigate. If the nutrient mix sits for a couple of hours before you use it check again prior to use.

 

[DogterB]

STOP. Do not use Tetra Aqua Safe in your nutrients or grow. It will bind to and remove all of the critical trace minerals needed by the plant.

Iron, Zinc, Copper, Selenium etc....................




Water absorbs carbon from the air this binds to calcium carbonate and it drops out of solution when exposed to air over time. This will change the PH of the water. RO water will grab a bunch of carbon when first exposed to air and can drop from~7PH to 4.5 in short order.

I aerate my water at least overnight with an air stone/pump before I use it. Mix the nutrients PH to the desired level. Then fertigate. If the nutrient mix sits for a couple of hours before you use it check again prior to use.

I haven't aerated my tap water, but can definitely start. I was actually thinking about adding aeration to my reservoir outside of the tent, or the float valve bucket within the tent. What do you think? I also don't add nutrients to my water for the SIP, but I do top-feed some and use tea on occasion.

 

[N/A-Greengo]

STOP. Do not use Tetra Aqua Safe in your nutrients or grow. It will bind to and remove all of the critical trace minerals needed by the plant.

Iron, Zinc, Copper, Selenium etc....................

Personally, I'm fine with that... Especially Lead. Used it for years...