My Setup.
The grow is an indoor Biobizz All-mix Soil grow.
The Strain is Unknown bagseed, which looks like a mix of indica/sativa.
Plants are 65 days old, in their 4th week of flowering.
Lights are 600w HPS and 1x 125w blue cfl. Lights are 10in from the smallest plant (in the middle of the light) and the tallest are growing past the light on the edge and I have an oscillating fan blowing right between the light and tops of plants. I have done the back of the hand test and i can hold my hand where the plants are with no discomfort and none of the plants seem to be showing burnt leaf tips or anything.
I feed the plants when the soil is dry (not too dry though) which turns out to be every second day. I am following the biobizz schedule for the all-mix soil.
At the moment I am feeding 1 ml/litre of bio-grow and 3 ml/litre bio-bloom and 2 ½ level tablespoons of molasses(non-sulphured) per 5litres water, for the past 3 feeds I have also been adding 1 level tablespoon of Epsom salts per the 5litres of water thinking that it was an MG def. Also a week ago I tried 2ml/litre bio-grow for extra Nitrogen in case it was an N deficiency.
The ph of the feed is between 6.5-6.7 of feed is no more no less. Im using a Milwaukee pH 600 digital tester. The runoff is always .2 higher then the feed(6.7-6.9). The water is left out for about 12 hours to evaporate the chlorine before going into the plant.
Temps in room are 25 degrees C to 30 degrees C during the day (depending on outside temps), never goes above 30C, then 20-25 degrees C at night.
Humidity is 40%-60%.
Yellowing of lower leaves started between 1st- 2nd week of flowering and has got progressively worse, but only on about 3-4 of the plants. Now it seems to be spreading to the other plants from what I can see and a lot of leaves are dropping off. I know during flowering they are supposed to yellow a bit, but this is spreading all the way up the plant on some of the plants and im not sure there will be any green left on any of the leaves before it finishes which will surely effect how the plant can use the light etc. Ive only started using Epsom salts the past 3 feeds (6 days) and because the bad pants are so yellow im finding it very hard to see if its making a difference at all. I “think” ive narrowed the problem down to either a Nitrogen or Magnesium deficiency, but I haven’t ruled out Iron deficiency or possibly Sulphur deficiency (though that usually starts with young leaves not the bottom ones). Ive read that “If the starting water is above 200 ppm, that is pretty hard water, that will lock out mg with all of the calcium in the water”, i do have hardwater afaik, could this be it?
Can anyone shed some light on this? What should I do?
How can you identify the difference between Nitrogen or Magnesium deficiency when it is widespread already?
Also does salt build-up in the soil always manifest itself by very high or very lo PH of the runoff water? Or can you have a salt build-up in the soil and still have good ph of the runoff water?
19 aug: just fed with 10ml grow, 15ml bloom, 3/4 tablespoon epsom salts and 2 tablespoons molasses all in 5litres water, all ph balanced to 6.6.
PS sorry for the long post
and crap pics (i only have a cameraphone).
Any help appriciated as some plants 70-80% yellow and lots of leaves dropping off over time
The grow is an indoor Biobizz All-mix Soil grow.
The Strain is Unknown bagseed, which looks like a mix of indica/sativa.
Plants are 65 days old, in their 4th week of flowering.
Lights are 600w HPS and 1x 125w blue cfl. Lights are 10in from the smallest plant (in the middle of the light) and the tallest are growing past the light on the edge and I have an oscillating fan blowing right between the light and tops of plants. I have done the back of the hand test and i can hold my hand where the plants are with no discomfort and none of the plants seem to be showing burnt leaf tips or anything.
I feed the plants when the soil is dry (not too dry though) which turns out to be every second day. I am following the biobizz schedule for the all-mix soil.
At the moment I am feeding 1 ml/litre of bio-grow and 3 ml/litre bio-bloom and 2 ½ level tablespoons of molasses(non-sulphured) per 5litres water, for the past 3 feeds I have also been adding 1 level tablespoon of Epsom salts per the 5litres of water thinking that it was an MG def. Also a week ago I tried 2ml/litre bio-grow for extra Nitrogen in case it was an N deficiency.
The ph of the feed is between 6.5-6.7 of feed is no more no less. Im using a Milwaukee pH 600 digital tester. The runoff is always .2 higher then the feed(6.7-6.9). The water is left out for about 12 hours to evaporate the chlorine before going into the plant.
Temps in room are 25 degrees C to 30 degrees C during the day (depending on outside temps), never goes above 30C, then 20-25 degrees C at night.
Humidity is 40%-60%.
Yellowing of lower leaves started between 1st- 2nd week of flowering and has got progressively worse, but only on about 3-4 of the plants. Now it seems to be spreading to the other plants from what I can see and a lot of leaves are dropping off. I know during flowering they are supposed to yellow a bit, but this is spreading all the way up the plant on some of the plants and im not sure there will be any green left on any of the leaves before it finishes which will surely effect how the plant can use the light etc. Ive only started using Epsom salts the past 3 feeds (6 days) and because the bad pants are so yellow im finding it very hard to see if its making a difference at all. I “think” ive narrowed the problem down to either a Nitrogen or Magnesium deficiency, but I haven’t ruled out Iron deficiency or possibly Sulphur deficiency (though that usually starts with young leaves not the bottom ones). Ive read that “If the starting water is above 200 ppm, that is pretty hard water, that will lock out mg with all of the calcium in the water”, i do have hardwater afaik, could this be it?
Can anyone shed some light on this? What should I do?
How can you identify the difference between Nitrogen or Magnesium deficiency when it is widespread already?
Also does salt build-up in the soil always manifest itself by very high or very lo PH of the runoff water? Or can you have a salt build-up in the soil and still have good ph of the runoff water?
19 aug: just fed with 10ml grow, 15ml bloom, 3/4 tablespoon epsom salts and 2 tablespoons molasses all in 5litres water, all ph balanced to 6.6.
PS sorry for the long post
and crap pics (i only have a cameraphone).Any help appriciated as some plants 70-80% yellow and lots of leaves dropping off over time
