View Full Version : General Hydroponics Feeding chart

05-24-2008, 02:06 AM
Although I do not use GH anymore, I think that they are wonderful products and I see that many of our members do use them. I was doing some research and came across this GH flora feeding chart and decided to post it as i am sure someone can make use of it.


05-24-2008, 03:50 AM
thanks Massproducer. i use GH Flora Nova nutes , and this is some pretty powerful stuff. i use only half of what is called for with so far descent results. although this is my first grow using these nutes , and i still need a few of thier other goodies , but i can see the potential of this product.

lowrys girl
05-24-2008, 04:07 AM
very good info in all if you are using gh and whoever is you might to want to look into the lucas formula i think thats what it was called lol yea works every time

05-24-2008, 04:19 AM
Lucas Formula

General Hydroponics Flora Series Feeding Strategy - Lucas Formula

G-M-B (Grow-Micro-Bloom)
0-5-10 - For Vegetative cycle (18/6)
0-8-16 - For Flowering cycle (12/12)

The numbers above indicate the number of milliliters (ml) of Flora Grow, Micro or Bloom formulas that I use in one gallon (US Liquid) of nutrients.

You will notice I dont use any of the Flora “Grow” formula, do not need to, the Flora "Micro" provides plenty of Nitrogen.

There are two ways to work with this formula:

1. Top off the reservoir daily using a pH corrected water solution as required to maintain full reservoir level. After adding back an amount of water equal to the amount of your reservoir capacity you should change the reservoir and put in fresh solution.

2. Top off the reservoir daily using a pH corrected 100% strength nutrient solution as required to maintain full reservoir level. Continue to use this nutrient solution without dumping the tank unless the PPM rises above acceptable levels.

Between vegetative and flowering cycles you should dump your nutrients, then flush (possibly with Clearex) to remove salt buildups, then change to the other feeding program. Always shake your GH nutrient bottles before using them!

For young plants, just transplanted into the hydro setup, give them 50% strength nutrient mix to prevent overfeeding them while their young. Gradually bring up the mix to full strength as they grow over the next few weeks or so.

The lucas formula is normally intended for use with RO or near 0 PPM water.

NOTE: The Lucas formula eliminates the need for Epsom salts to correct (Magnesium) Mg deficiencies in most normal feeding programs recommended by manufacturers. Cannabis needs a lot of Magnesium to thrive.

The Flora Micro is providing the Nitrogen and the Magnesium in the proper balance, thus there is no need for the Grow formula and little or no room under the maximum acceptable ppm limit of 1600 @ 0.7 conversion.

Calculated EC/TDS levels:

EC microsiemen:
0-4-8: 946 ÁS
0-5-10: 1184 ÁS
0-8-16: 1894 ÁS

TDS @ 0.5 conversion:
0-4-8 = 473 ppm
0-5-10 = 592 ppm
0-8-16 = 947 ppm

TDS @ 0.7 conversion:
0-4-8 = 663 ppm
0-5-10 = 829 ppm
0-8-16 = 1326 ppm

Addback Calculator - (For Advanced Users)

Say you were running the 0-8-16 formula, at 0.7 conversion with a 22 gallon res. When you first fill it up, your ppm will be around 1330.

Now you have been growing for a week, and some of the water has been taken up by the plants, some has evaporated, and now your res is at 947 ppm. You need to get your ppm from 947 to 1330. Here is the equation:

((target - current) / target) * 8 ml per gallon * res gallons = Flora Micro (ml) double this figure to get Flora Bloom (ml)


((1330 - 947) / 1330) * 8 * 22
(383 / 1330) * 8 * 22
0.3 * 8 * 22 = 53 ml Flora Micro

53 ml Flora Micro, double that and you get 106 ml Flora Bloom. So 53 ml Flora Micro and 106 ml Flora Bloom to add back to your 22 gallon res to get you from 947 to 1330.

10-14-2008, 09:30 PM
I agree the chart does seem to high for us too, use less and watch your plants leaves, we only raise the nutes once a week or every ten days. we use half of what it says to use.

10-14-2008, 09:54 PM
Check out this link it has Feeding Charts for several diffent products.


10-14-2008, 11:09 PM
thanks mass,good product.

Puffin Afatty
10-14-2008, 11:27 PM
I used the formula for a long while with excellent results, keeping an ec of 1.5-1.8 for most strains and a ph of 5.5- 5.8

10-14-2008, 11:40 PM
works for me puffin,i use the lucas formula.no complaints either.hell with buying all the extra hoopla

10-15-2008, 02:51 PM
one sativa plant 9 oz, with flora green and bloom, indicas the highest wieght so far 3.5 oz, this includes the use of kool bloom at last three weeks. Seeds from gypsy nirvana, ice and blue mystic...First plant the sativa was a thai cross and northern lights.