Hydroponics first time — calcium deficiency?

I don’t know all the technical lingo yet so please forgive me, first time grower here
Strain is white widow autoflower from ILGM
using a AeroGarden farm XL in a 2x2x4 tent
Capacity ~1.5 gallon
Day 22
Using an air stone 24/7, 3.2L per minute
Temp kept between 69-78 F
pH at 6.3, stable
Using GH flora series, Calimag, botanicare hydroguard
TDS at 700

I’m getting these terrible spots on fan leaves that seemed like calcium deficiency from searching online but it doesn’t seem to be getting any better and it sounds like it’s abnormal for a cal deficiency to show up this early (from what I’ve read on other posts)
Is this something else?



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First noticed the issue like 12 days in, here is a picture from day 16


I’ve tried adding additional cal mag for a week+ but it hasn’t fixed the issue. I was following a guide that recommended to use half the gh flora series schedule (2.5 ML per gallon instead of 5). After reviewing more information I’m wondering if it’s a different deficiency?

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I’m having a similar issue with a couple super skunk autos right now. Or I “had” an issue, I think… maybe… At any rate, I’ll be tagging along to see what the real pros say. Figured I’d at least throw my reply in to keep the thread moving :grin:
Oh, and welcome to the farm!!

If I did indeed correct it, I caught it a bit earlier, but the red petioles, blue/gray areas/spots, turning rusty then dying off… looked like a phosphorous problem to me. Woke up one morning and it hit overnight. Kept getting worse all morning, added a couple ml/g of Bloom (from 5m/5g/5b to 5/5/7) and by evening it seemed under control. That was yesterday, hasn’t gotten any worse yet :crossed_fingers:

I’d work your pH down at least a little though. 5.8 is the suggested “ideal” for hydro, but that might be a bit of a shock at once.

For your GH nutes, were you running 5/5/5 and then switched to half strength? Was this happening then too? I’ve also read calcium can be antagonistic towards phosphorous uptake, not sure on all that, but that by adding more calcium, it might be compounding the problem if indeed it is a phosphorous issue.

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I had read somewhere else that too low a pH could prevent calcium intake (something or other) so I was trying to keep it from getting below 6 but I’m not really sure, I can definitely see how adding too much cal mag to compensate might’ve made it worse so I drained the garden and restarted with fresh nutes. Tbh I don’t even know which bottles contain what nutrients yet, but you’re saying the flora bloom has the phosphorus to possibly fix it? I was looking at a chart of deficiencies and it did look right.

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Yes, 5% phosphate is in Bloom @Reimaker

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Added another 3ml/gallon, will see if the problem continues to grow or slows down, much appreciated. Gonna go with the 5/5/7 moving forward

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Welcome my freind.
Hydroponic ph should be 5.8 with cannabis.
Heres a chart showing nutrient uptake at different ph levels.


As you see on the chart, Calcium, manganese, iron, and boron are not going to be taken up well if any at anything higher then 5.8ph.

A ph drift upwards over time is pretty common and most growers will ph back down to 5.8 once ph drifts upto 6.2

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Hi! I’m a newbie also, my first grow, and am having the same issue. I’m in week 4. It seems like we are using the same products, aerogarden, flora series, etc. My ph was 6.4, which appears to be too high (pun intended), and my fan leaves seem to be headed the same way as yours. I guess I’ll flush everything and start over. Any other suggestions 1HappyPappy or Reimaker?

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For me keeping the pH as close as possible to 5.8 has really helped. I pruned the damaged leaves and not seeing spots on the newer ones (but as you can see mine were really bad). How often are you changing the water/nutrients? And how much calmag are you using in your solution?

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Very well could be ph related.
Some plant’s seem to do fine with more drift then others but trying to keep it at 5.8 is best no higher then 6.2. It kinda “bouncing” from 5.8 to 6.2 insures in should have access to all the nutrients.

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I changed the water and nutrients yesterday for the time. I added 1 tsp/gal of the calmag, 2 ml of hydroguard, along with the flora products. And this time I kept the ph @5.8. This morning it seems as if it likes what I did. Maybe part of my problem is that I didn’t add any additional nutes after planting, and it’s now week four. Now that I’ve done more research, I think I should have been feeding every week. The plants were probably starving. Thanks for the help and I’ll keep you posted.

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Yes, GH expects you to completely dump and refill every week with a schedule roughly drafted around one of their examples (light, med, aggressive). That’s always seemed like a huge waste of nutes to me, but it is what it is, so I keep my res volumes low and stretch out changes when I can. Even so, the solution will get pretty funky after a couple weeks, and then you start asking for root diseases, deficiencies, pH spikes, etc. So once a week isn’t wrong, but it can be cheated a little. More at some times, less at others.

If deficiency issues come up between changes, you can get away with boosting the gro or bloom a couple ml/g, but if I want to boost the micro or calmag, I do a complete dump, or there’s a risk of nutrient lockout from how I understand it. (That’s why it’s so imperative to add micro first when adding the trio, then there’s some degree of conflict over whether gro or bloom should be next, so it’s apparently not as big a deal - ArmorSi and CalMag have to be before flora trio though)
…Or just dump some out and replace with straight water to go the other way.

This is their aggressive table, autos might do better on a lighter table.

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@Bubbala I really appreciate the knowledge. I’m planning to keep growing hydro so all the help I can get from you all and other growers is so helpful!

To recap: change water every week with fresh nutes, check ph daily, keep ph @5.8, if boosting micro or calmag completely dump.

I’ve read that a TDS meter is not necessary to use, only ph meter. What are the thoughts from the group?

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I use a tds meter when I’m mixing my nutrient solution but haven’t really gleaned any important information from it, I think in general it can tell you if you’re way too high or low but it doesn’t break it down as far as components so :man_shrugging:

As far as changing the water every week, if you have a bounty the volume is only around a gallon anyway so not like you’d be burning through nutes since I’m guessing you only have 1 or 2 plants that can fit (I have the farm xl and already seeing crowding in week 4

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Good info about the TDS meter. Yep, I have two Bounty Elites with one plant in each. The water dump won’t be a problem.

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I do (R)DWC, so I have buckets and reservoirs. I check TDS when I first get everything running again after a change over, but I go by liquid measurements (ml/g) to know what to feed. Knowing what my TDS is after a change over though, gives me a benchmark to monitor as I add water &/or solution between change overs as plants get bigger.
It doesn’t sound like that particular aspect really pertains to your situation though.

The flip side, is TDS meters are pretty cheap, unlike a decent pH meter.

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I was thinking that I’d get a TDS meter and see if it helps me. If it doesn’t help, I haven’t wasted much money on it. Maybe just to see the difference in the weekly water dumps. Since it doesn’t tell me what nutes I need to add or cut back on, I can’t see another reason to have it.

In this case, it’s kinda one of those tools that you won’t really need, until you start troubleshooting a problem. It may not measure contents individually, but it’s the only way to measure the total of the finished mix.

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Got it. Thanks!

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So I see people mention pH creeping up a lot, I’ve noticed mine keeps creeping downward lately, anything to that?