Brown/Black spots all over fan leaves spreading very rapidly! PLEASE HELP

ucross58 · #1 11-25-2007, 07:59 PM

If you look at the picture below i have no idea what is causing this to happen i am using veg/micro nutes in a 50 gal res changed once a week, the lighting cycle is 24 hours they are in their 4th week of veging someone please help

bwinn27 · #2 11-25-2007, 08:09 PM

are you using nuts? or could be bugs. do you have a ph tester?

bwinn27 · #3 11-25-2007, 08:12 PM

sorry you do use nuts how long have you been using them.

Blazin420Haze · #4 11-25-2007, 08:19 PM

Flush First If it not better the next day than it can be

Calcium Def Or

Magnesium (Mg) deficiency.
Magnesium deficiency will exhibit a yellowing (which may turn brown) and interveinal chlorosis beginning in the older leaves. The older leaves will be the first to develop interveinal chlorosis. Starting at leaf margin or tip and progressing inward between the veins. Notice how the veins remain somewhat green. the leaves curl upwards like they're praying? They're praying for Mg! The tips may also twist.

This can be quickly resolved by watering with 1 tablespoon Epsom salts/gallon of water. Until you can correct nutrient lockout, try foliar feeding. That way the plants get all the nitrogen and Mg they need. The plants can be foliar feed at ½ teaspoon/quart of Epsom salts (first powdered and dissolved in some hot water). When mixing up soil, use 2 teaspoon dolomite lime per gallon of soil.
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. Either add a 1/4 teaspoon per gallon of epsom salts or lime (both will effectively reduce the lockout or invest into a reverse osmosis water filter.
Mg can get locked-up by too much Ca, Cl or ammonium nitrogen. Don't overdo Mg or you'll lock up other nutrients.

ucross58 · #5 11-25-2007, 08:45 PM

the plants sit in a 50 gal resvoir, so would you suggest flushing the system, or adding the epsom salt, also you said 1 tablespoon of salt per gallon of water. well the tank i fell with about 40 gallons, so is that 40 tablespoons?

ucross58 · #6 11-25-2007, 08:47 PM

also ph is between, 6.2 and 6.7 so that has been steady for about a week, the water temp is 72 farenheit

ucross58 · #7 11-25-2007, 08:48 PM

one more thing, out of the 6 none of the other ones are experiencing the same thing, all other girls are 100% minus the bottom very little leaves turned brown and died then fell off

ucross58 · #8 11-26-2007, 09:45 AM

I think it was nute burn fellas, tell me this if you are familiar with stealth hydro company they send those packets out with the system, i used almost 2 packets per 40 gallons of water along with 2 packets of micro nutes, could this have been a definet over feeding?

storzbickel · #9 11-26-2007, 10:29 AM

i had a simliar thing happen to my plants and im pretty postivie it was Mg deficiency. i took Blazins' advice that i saw on another post and treated with epsom salts. This was 2 days ago and my plants are showing some recovery signs.

i have also had an issue like this with my soil plants, and pH was the simple issue. i flushed with pHed water and tested the run off.

I do not know about Stealth hydro. but i do know that with my system, the aerogarden, it comes with nute tablets.

on other posts ive read that the nutes are wayy to hot and damage the plants. You may want to look into what nutes you are using- if they are for specific plants, like peppers, salad green etc, the nutes probably arent what you are looking for.

you say they are "packets" so it doesnt sound like liquid. if you continue with those nutes you may need to decrease the strength and that may avoid any more burning.

FoxFarm is all over this site with good results. They sell a 3 part hydroponic nute kit. Remember to dilute properly (i.e 1/4 recommended stength to start out). For my aerogarden i am using Advanced Nutrients : Vitaboost Pro, and Iguana Juice