Deficiency or excess
 

Can anyone tell me what's wrong? [IMG]https://farm2.staticflickr.com/1481/...10006626_h.jpgdeficiency or excess? by Stan Furman, on Flickr[/IMG]

Re: Deficiency or excess
 

Hi tanksalot,

My first thought is an iron deficiency with the interveinal chlorosis (yellow areas between green leaf veins) however usually only the younger leaves are effect. The second possibility would be a potassium deficiency which usually exhibits chlorotic and then burn areas along the margins of older leaves.

What are you dosing for fertilizer?

Re: Deficiency or excess
 

I've been trying to get a handle on the tank's requirements, and have been dosing as needed using pps classic formulas and have been testing fairly regularly. I've added KNO3 & K2SO4 when the nitrates were low (recently). I had also added MgSO4 earlier because somewhere I read that the "veining" was due to a magnesium deficiency. I use CSM+B for iron/trace. Fe runs from 0.1 - 0.25 ppm.

Re: Deficiency or excess
 

What are "burn areas along the margins of older leaves"? Many of the leaves seem to have a red margin on the outside of the leaf.

Re: Deficiency or excess
 

Hi tanksalot,

I used to dose using the PPS-Pro method but I found myself constantly battling deficiencies of one sort or another. I switched to Estimative Index (EI) dosing and have not had anywhere near the number of issues.

Tom Barr advises that there is a 'misconception' that the target level for Fe is 0.1ppm; he states that he typically targets 1.0ppm of Fe for his tanks. I would start by kicking up the iron.

Sorry, it is difficult to see from the pictures but the leaf margins looked brown and dying to me, not red - my error.