Hi,

90gal tank is about 1 month old. My dosing:

KNO3: 8.5g=1.5tsp=15ppm, 3x

KH2PO4: 1.5g=0.3tsp=3ppm, 3x

K2SO4: 10g=1.7tsp=13ppm, 3x

[total K+ being added = 22ppm, 3x]

TPN: 20ml, 3x

GH Booster: 4 tsp, 1x (tap GH=zero)

Ca/Mg: not adding any

Iron: still figuring out how to dose; recently increased to 1.0 ppm, 3x

Excel: dose at 1.5x recommended dose, usually every day

Lighting: 4x55 CF (4hrs 110w + 2hrs 220w + 4hrs 110w)

I noticed small holes in lower leaves of Hygrophila corymbosa angustifolia, typically suggested to be a sign of K+ deficiency. With current dosing, I am adding 22ppm K+, 3x per week (K+ from KNO3 plus K+ from K2SO4).

When I started the tank I decided to dose extra K+ from K2SO4 which is often suggested as unnecessary, just to make sure my EI target K+ would be around 20ppm. With holes in anguistifolia as evidence of K+ deficiency, how much more should I bump K+ up?

Current intention is to change from 10g (1.7tsp) to 20g (3.3tsp) K2SO4, 3x. This change would mean I am adding 35ppm K+, 3x per week (from 8.5g KNO3 plus 20g K2SO4).

thanks,

growitnow

90gal tank is about 1 month old. My dosing:

KNO3: 8.5g=1.5tsp=15ppm, 3x

KH2PO4: 1.5g=0.3tsp=3ppm, 3x

K2SO4: 10g=1.7tsp=13ppm, 3x

[total K+ being added = 22ppm, 3x]

TPN: 20ml, 3x

GH Booster: 4 tsp, 1x (tap GH=zero)

Ca/Mg: not adding any

Iron: still figuring out how to dose; recently increased to 1.0 ppm, 3x

Excel: dose at 1.5x recommended dose, usually every day

Lighting: 4x55 CF (4hrs 110w + 2hrs 220w + 4hrs 110w)

I noticed small holes in lower leaves of Hygrophila corymbosa angustifolia, typically suggested to be a sign of K+ deficiency. With current dosing, I am adding 22ppm K+, 3x per week (K+ from KNO3 plus K+ from K2SO4).

When I started the tank I decided to dose extra K+ from K2SO4 which is often suggested as unnecessary, just to make sure my EI target K+ would be around 20ppm. With holes in anguistifolia as evidence of K+ deficiency, how much more should I bump K+ up?

Current intention is to change from 10g (1.7tsp) to 20g (3.3tsp) K2SO4, 3x. This change would mean I am adding 35ppm K+, 3x per week (from 8.5g KNO3 plus 20g K2SO4).

thanks,

growitnow

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