What's funny is that if you think of letting the lettuce have two weeks as seedlings, then four weeks to grow, the flushing period was in that last fourth week (so it's not like the plants were setting around for an extra week), and still there was VERY significant growth that occurred during that week. I guess it really was using up leftover nutrients :) But then again I also made a PH correction - I had it at 5.5 and learned it should be 6.0 so maybe that did something too.

Now that I have a smaller reservoir as in another post I made tonight, (5 gallon bucket) I will be able to flush more easily and cheaply the way they recommend - with the sugary substitute and the calcium/iron substitute for three days, then four days with water - supposedly that makes it even better.

Flushing will be fine for crops that come to maturity, but, I long for an herb garden that will taste good picking it at any time like I would outdoors. I wonder how the aero garden tastes at any point in time and what nutrients it uses.

The link below will let you see a handy conversion chart for various volume measures in case you need to make bigger (or smaller) batches.

I guess I don't know much about miracle grow though so I need to start there. Thanks!

I could not imagine harvesting lettuce from my regular garden, shaking off the dirt from the roots, and then starving it by giving it only water for a week before eating it, and expect it to taste better.

Do we not all agree that the chemical nutrients we are putting in our hydroponics systems are only refined versions of what is in the ground already? I thought we all believed that those chemicals were GOOD things. Where am I going wrong here? If anyone thought the nutrients were bad for humans, they'd stick with regular gardening, right? Why do hydroponics in the first place if you believe well fed plants don't taste good or are somehow bad for you?

Perhaps there is still something about organic dirt gardens vs. our standard hydroponic setups that is different from a standpoint of flushing and taste. I don't know.

Here is a website - I haven't read it all yet but maybe it's a description of what needs to be checked out:
http://www.1-hydroponics.co.uk/transcript-growth-cycles.htm

Quote:

"
You will find at this point, 3 weeks before harvest, the plants are going to be sucking up a whole tank at least a tank a week. So, you’re going to be filling up that tank possibly on a daily, or a bi-daily basis. And once you’ve filled it up over the course of the week, then go back on to your [picks up bottles] Bloom A and your Bloom B and not using your PK13/14 anymore. At that point, when you’re 1 week away from harvesting, 1 week away from cropping your plants, what we highly recommend doing is emptying out the reservoir, filling the reservoir up with nothing but clean water, ph adjust it to a ph of 6 and then feed the plants nothing but clean water for 1 week. This is what they call flushing.

It benefits multi levels. One it benefits the system because it gets rid of any nutrient build up in the pebbles themselves, two it benefits the plant because it actually encourages the plant to take all the nutrient out of it, itself. If you’re growing fruit or veg, or any plant that is consumed, if you don’t flush it at the end in a hydroponic system, you end up [picks up bottles] with an excessive amount of nutrient build up in the plant and that can make the plant taste quite bitter. So it’s fundamental to flush the system and the plants for 1 week before harvest and that point you’re ready to crop the plants and start again. Job done.
"

I will give this a try once my tomato plant / or lettuce are ready (in a month or two)