Late flowering illness.. Calcium? plase help.

[x00m]

-Problem: dots and blotches on upper healthy leaves....

-Medium/grow method: RDCW

-Feed and supplements used: Dutch Pro Auto Bloom A/B & Dutch Pro Explode. 600ppm in total

-Water source: Tap water softwater (clean good water from the scottish mountains)

-Strain and age: Meant to be Auto Speed bud.. but this is its 4th month.. didnt start to flower until i switched to 12/12 lighting.

-Climate: Temp sustained at 22.5c RH is 50%-60%

- Light used: 12/12 LED (chinese) using FLOWER mode only.. not FLOWER & VEG

-Additional info: Possibly the last 2 weeks... very slow progression, but its progressing...


--Pictures

 

[Mañ'O'Green]

It is hard to get plants across the finish line in DWC after 4 months or more without the elements in the reservoir getting out of balance at some point. It looks as though that is what has happened here. Have you maintained a steady water level in the reservoir? Are you changing it weekly? You have not talked about PH are you holding that from 5.6 to 6.2 PH? What are you using to adjust it. Are you running HydroGuard?

The bud booster is mostly Potassium so you may be getting too much simply because of how long you have been using it?

You state your climate is steady at 22.5°C even at lights off? that is on the low side for daytime?

The plants look almost done so there may not be much to do about this. Realistically you have done a good job

 

[x00m]

It is hard to get plants across the finish line in DWC after 4 months or more without the elements in the reservoir getting out of balance at some point. It looks as though that is what has happened here. Have you maintained a steady water level in the reservoir? Are you changing it weekly? You have not talked about PH are you holding that from 5.6 to 6.2 PH? What are you using to adjust it. Are you running HydroGuard?

The bud booster is mostly Potassium so you may be getting too much simply because of how long you have been using it?

You state your climate is steady at 22.5°C even at lights off? that is on the low side for daytime?

The plants look almost done so there may not be much to do about this. Realistically you have done a good job

Apologies yes! the pH... it is at 5.8 but it does drift quite drastically if im being honest... it keeps dropping to 5.25 every day. so i add dutch pro ph + and wait for it to stablize for 20 minutes check back and its around 5.8 - 6.0 then next morning... its back down to 5.25 or there abouts...

for temperature i keep it at 22.5c every day and night. I live in a cold climate at the moment and the ambient is about 13c in the shed. so i use a heater with a temp sensor to switch it on when it drops to 20.5c to raise it back to 22.5c...should the temps be higher during day than during night? i wouldnt have thought it mattered. But learn something new every day!

i do change the water... not once a week though.. i aim for every 1 and a half weeks to 2 weeks... should i narrow this down and do it once a week instead?

i top up the reservoir almost daily as the plant is drinking a lot of juice now.

 

[Mañ'O'Green]

Apologies yes! the pH... it is at 5.8 but it does drift quite drastically if im being honest... it keeps dropping to 5.25 every day. so i add dutch pro ph + and wait for it to stablize for 20 minutes check back and its around 5.8 - 6.0 then next morning... its back down to 5.25 or there abouts...

for temperature i keep it at 22.5c every day and night. I live in a cold climate at the moment and the ambient is about 13c in the shed. so i use a heater with a temp sensor to switch it on when it drops to 20.5c to raise it back to 22.5c...should the temps be higher during day than during night? i wouldnt have thought it mattered. But learn something new every day!

i do change the water... not once a week though.. i aim for every 1 and a half weeks to 2 weeks... should i narrow this down and do it once a week instead?

i top up the reservoir almost daily as the plant is drinking a lot of juice now.

Ok I understand your temperature situation now. That is a little bit low at 20.5 and the plant will grow and ripen a little slower but should be ok.

Yes change weekly especially when the plant is in flower and using a lot of liquid. Your water is an unknown to me. Do you have any idea what is actually in it? It makes a difference in hydroponics much more than in soil.

5.25 PH is much too low. You would be ok to start at 6.3 to see if you can keep it from dropping below 5.6 at night. Perhaps you should aerate your water for a day or two before using it. This PH drop usually happens when there is a lot of calcium carbonate in the water to start with. This is contrary to the soft water you say you are starting with?

 

[x00m]

All i know is that my water is about 40ppm out of the tap. no chlorine either.

okay i will raise the ph higher to accomodate the drop over night. ill change water sometime today as well, then ill do it weekly.

i can also raise my temperature to better suit the plant.

 

[DCLXVI]

OMG.. bruh (did I use that right?, my grandkids hate when I say it)... MoG said:

Realistically you have done a good job

 

[x00m]

Ok I understand your temperature situation now. That is a little bit low at 20.5 and the plant will grow and ripen a little slower but should be ok.

Yes change weekly especially when the plant is in flower and using a lot of liquid. Your water is an unknown to me. Do you have any idea what is actually in it? It makes a difference in hydroponics much more than in soil.

5.25 PH is much too low. You would be ok to start at 6.3 to see if you can keep it from dropping below 5.6 at night. Perhaps you should aerate your water for a day or two before using it. This PH drop usually happens when there is a lot of calcium carbonate in the water to start with. This is contrary to the soft water you say you are starting with?

I need to correct an information i gave which was prety wrong... i thought my RH was around 45-55%... but its way...WAY below that... it is actually 25-26%... and has been so throughout the entire life of this plant. I only just noticied this. My hygrometer was low on battery and it was giving me fasle info. Replaced the batteries and let it stablize for around 12 hours and it is now at 25-26%....

how can i increase this? and is this why my plants leaves are dying?

 

[THE BEAR]

Dam hygrometers, I had the same problem, was stuck on 44%\ 21°© for ages, so I set it on top of the reflector hood for 5 mins and it just stayed the same, so I
Upgraded to a weather station were you put the wireless sensor in the tent, and can keep an eye on Rh and temps from my living room on a display sceen,

 

[Bill.de.Cat]

Lol, that's why I got 2 of those cheap ebay temp/RH things in the tent. Ever go wrong with redundancy

 

[Mañ'O'Green]

I need to correct an information i gave which was prety wrong... i thought my RH was around 45-55%... but its way...WAY below that... it is actually 25-26%... and has been so throughout the entire life of this plant. I only just noticied this. My hygrometer was low on battery and it was giving me fasle info. Replaced the batteries and let it stablize for around 12 hours and it is now at 25-26%....

how can i increase this? and is this why my plants leaves are dying?

Yes this alone can be the source of all manor of problems. A wet towel with one end in a bucket of water and the fan blowing across it will help. A sonic humidifierer can help or one like I use: