Leaf spots??

[Wesleyterrier]

I’m currently just over two weeks in flower and one of the plants has developed spots  on its leaves. The other three plants are fine with no spots any where. The spots seem quite sporadic with some at the top and some at the bottom. Overall the plant looks in good condition I just want to make sure it’s not missing out or being overfed. 
Currently all plants are fed through topspin drippers so are all receiving the same amount of food/ water, 10 litres per 4 plants every other day. 
The plants are in bio-bizz all mix and are being fed 1ml silicon, 1ml top max, 1ml bio grow and 2ml or bio bloom per litre , I add 0.1g of magnesium per litre to balance the cal mag ratio to 3:1 as on moderately hard water. 

The environment seems okay with roots staying around 24 degrees, lights on temps 27-28 with humidity 50-60%. Lights off temps are 26-27 with 40-50% humidity. 
Any suggestions appreciated, atb.

[Military Grade]

Your environment looks in check, so I'd guess it was either feeds,water or medium.

 

Have you had the water tested or winging the Magnesium dosage?

 

I try not to use All mix myself, I've had some strain react badly to it, light mix gives you more control over the variables.

 

It does look like a classic early flower mag problem, but it's finding the root of why Magnesium is not being taken up properly.

[Wesleyterrier]

5 minutes ago, Military Grade said:

Your environment looks in check, so I'd guess it was either feeds,water or medium.

 

Have you had the water tested or winging the Magnesium dosage?

 

I try not to use All mix myself, I've had some strain react badly to it, light mix gives you more control over the variables.

 

It does look like a classic early flower mag problem, but it's finding the root of why Magnesium is not being taken up properly.

Thanks @Military Grade, I have just gone off the water companies average for my area water supply. I know it’s river sourced so is moderately hard with fluctuating chlorine levels ( I work for said water company). It feels like a mag deficiency or lock out but can’t put finger on it as the other 3 plants are perfect. It might have started from a suspected nitrogen deficiency from under watering. I may be over feeding the mag and causing a lock out so will not add any for a few feeds and see how it goes. Atb

[Military Grade]

Letting the soil dry out too much too many times can cause uptake problems with most Nutrients.

 

Just try not to change too much at once and give a bit time for any changes to take effect, and to help to narrow down what's working or not. Fingers crossed it just not enough Magnesium as that would be an easy fix.

 

I've been winging the mag dosage with my water for a couple of years now, I also live in the Chalky tundra of the UK , I've never measured the weight of Epsom salt I put in but it's about ¼ tea spoon of Epsom salts per litre, not sure if that helps at all but might give some extra perspective.

[Slippy One]

I get this in my bonsai cabinet when they grow too bushy for the circulation fan to be effective. Time for a prune I reckon.