Hydroponics (DWC) Newbie

[atulbaliga]

Thank You GPSFrontier for the valuable comments. Will work on the PH. As of today, the Lettuce has withered off and I am left with Bell Peppers. I will start another setup for Lettuce following your guidelines.
The sponge was purchased by a local hydroponics equipment manufacturer selling starter kits.

Your site http://www.homehydrosystems.com/ is my bible and have the nutrient requirement chart printed out for reference. I derived the need for PPM and PH from there. Guess its for older plants and for seedlings we should go by 1/4th rule

To give you more info of mysetup, here are the pics






For Bellpepper, I see a small root out of the sponge. Will monitor the progress and report back here.

[GpsFrontier]

I don't see any dome over it. If you put a disposable clear plastic party cup upside down over each of the seedlings it will help hold in the humidity. I would put a few small holes in each of the cup domes to allow fresh air to circulate from the bubbles underneath up into the cups and out the holes.

[GpsFrontier]

Hello atulbaliga,
I'm glad to hear you find my site useful, I try to update and add to it regularly.

Yes the values in the charts are for larger plants. The values in the charts are also only a starting point guide. There are lots of variables that will affect a plants nutrient uptake, and it would be impossible create a chart that could include every possible variable. Even the amount of light, temperature, and humidity will change how a plant uses nutrients. Not to mention the specific variety of the plant in any plant category. So the charts are meant to be a general starting point.

With pH, right around 6.0 really works for just about all hydroponically grown plants. Some plants may benefit from a little higher pH, like with peppers. Some spicy pepper plants increase heat with higher pH. But you never want to go above 7.0, and 6.6 is right on the edge of that. pH doesn't need to be exact, you just want to be within a range. Most plants fall between 5.5 and 6.5 for good nutrient uptake. So if you shoot for right in the middle at 6.0 it doesn't mater if it vears some. If your growing hot peppers and like them as hot as you can get them, closer to 6.5 while their fruiting could help that. But if it gets above 7.0 then the plants could suffer from nutrient deficiencies.

As for the nutrient concentrations and seedlings, yes absolutely, seedlings don't need full strength nutrients. That's kind of like giving a baby that eats baby food a 7 coarse meal. Theirs no way a baby could eat a 7 coarse meal. He would take a few bites and the rest would be in the trash. If he tried to eat it all, he would get sick or bloated. In fact for seedlings as small as the one's in the pictures you posted, I typically don't even use any nutrients at all until they reach that size. Then start with something like anywhere from 10% to 25% strength. Then in a week or two when they bigger, I'll increase it to about 50% strength, and so on....

[atulbaliga]

Want to provide an update on corrections and learning from the comments. I calibrated the PH to 6.0

[GpsFrontier]

Hello atulbaliga,
When you say calibrated pH, are you referring to calibrating a pH meter? Or adjusting the nutrient solution pH? I asked because I'm not sure what the liquid in the picture is. I assumed you were using a ph meter because because of the values you were giving, but the picture looks like the color you would get using pH drops at 6.0. So now I'm wondering if the picture is on the calibration fluid used to calibrate a pH meter, or of the pH drops test.


Also have you gotten the water temp down?

[atulbaliga]

Sorry for the confusion. I adjusted the nutrient solution to get the PH to 6.0. As a backup I also use the tetra PH test kit to verify and this pic is the output of the test after adjustment. PH meter needs frequent calibration as its a Chinese make and you know how reliable they are 😜

Water temp is still at 28 deg C and humidity has risen up to 78% RH. Planning to put a fan around to circulate the air and also cool the water.

[GpsFrontier]

Ya, I don't trust the meters, the drops are much more reliable and cost much less money, so I don't even bother with the pH meters. I would put some ice in that water to drop the water temp down another 10 degrees to about 72 F (22 C).