Are you having to adjust ph everyday?what are you using to adjust ph,and how many times do you adjust ph before doing a complete resevoir change?I ask cause your plants could be getting burned by an abundance of nutrients that make up the ph adjuster
From the pic it looks like the plants only have 3 or 4 nodes,maybe your nute solution is too strong.one of the more experienced users should chime in soon and help alot more than I probably can
Looks to be Manganese problem.
ph should be 5.0. 6.0 range.
Try any organic nutrient with manganese in it will fix your problem. Only use 1/2 strength or you could cause nut burn.
5.8 is the ideal target range for hydroponics, and Rob is trying to keep it there.
Very light green leaves and the fact that he is using such a low concentration of the original nutrient brand he was using probably contributed to the instability of the pH as well as the nutrient deficiencies. Sometimes half strength/quarter strength is the exact wrong thing to do.
Just switched nut’"s went from moon dust to General Hypo Floria Series. Did a 1/2 dose water change yesterday and just another at full strengh. Yes the Lime green color of the leafs has me concerned.
Uniform light green usually means not enough nitrogen. Too low of doses of any nutrient system could be part of the reason not enough nitrogen is available to the plants.
Having said that, most nutrient systems should have a feeding schedule that accounts for various phases of growth, and you should almost always follow the directions.
Unfortunately I don’t have any familiarity with the moon dust so I don’t know what the recommended nutrient concentrations should be at, but in general, a Parts Per Million or Electrical Conductivity reading of the reservoir can give us a better idea, an EC of 1.0 (or in the US conversion to parts per million is 500PPM) is usually enough to keep a stable pH and supply adequate nutrients to the plant without deficiencies, that is, in most balanced nutrient systems. General Hydroponics, I think, can run as low as 0.5-0.6EC/250-300PPM for seedlings and clones and such. EC or PPM is a broader measurement that can kind of cover the use of various nute systems, but it is always best to follow the directions.
Keep in mind, those are the numbers of a nutrient system mixed with distilled or R/O near or zero PPM water. If your water starts off with 200PPM, then you have to add that number to your final result. And some nutrient systems may be counting on your tap water supplying some of the common mineral nutrients found in most drinking water that are good for us and plants, often calcium and magnesium being some of the most often found in relative abundance in most tap water.
3 days on new nutrients (General Hydroponics Flora series) and growing much better and darker green color coming in. I still have hope. Anyone thinking of using ‘Moondust’ seriously think twice about it!