Your pH and TDS are only optimum for Tomatoes, but the Cucumbers need pH 5.5 and TDS 1190-1750. I recommend to plant the Cucumbers in separate line or trough and give them the proper pH and TDS.
Good luck in your growing.

That's good to know safwat! Is there a list out there somewhere that shows all the proper levels for various fruits and veggies grown with hydroponics? I'd love to know as much as possible without trial and error!

Howard Resh has some good articles on hydroponic vegetable growing on his web site, www.howardresh.com. There are lots of recipes out there on the web. I find the nutrient recommendations of hydrogardens in Colorado Springs to be quite good for my use. If Diva is bitter, it is usually because it is growing with a good bit of stress; you might try lowering the tds, and also looking at an alternative growing method; nft can be hard on cucumbers if there are excursions from their optimal nutrient levels.
Renais

charlielittle wrote:
Is there a list out there somewhere that shows all the proper levels for various fruits and veggies grown with hydroponics?

Try this link

Hi Charlielittle,
Here is a list of pH/PPM/CF for Various Vegetables.
Note that PPS=TDS, and if you divide CF values by 10 you get EC/mS-1. Please go to the following website:
www.gthydro.com/vegetables.html

Here is what I'd like to know:

Vegetables Ph category cF PPM
Tomatoes 6.0-6.5 H 20-50 1400-3500

The cF and the PPM seem to have such a large range. How do you choose?

Low side for starter plants and increase with plant growth and maturity. Takes experience I guess to know exact amounts for particular plant growth stages.

Wow my truncheon meter only goes up to 36 CF - 50 is off the chart :)

I will note, from the linked table, that capsicums show a nutrient requirement of 1260-1540 ppm. I have been growing chiles (capsicum) in hydro for years and the recommended nutrient is high by a factor of 3 or 4.

Chiles with this much nutrient show burn in 2 or 3 days.

Thanks for the info Willard. I wonder though if the ph and/or nutrient brand plays into it as well, regarding the PPM.

Here's a link to a chart on Vegetable PH and PPM.

-Mus

Here is a link that might be useful:

Cukes are a warm weather crop. I noticed that you said temp of solution was 60-68. Unless you are growing some cool weather type, I would guess the temp is too low.