I had some of that with my cucumbers in a modified NFT system. Actually I noticed a little of that in some of my dirt cucumbers too. I'm not sure but I wonder if it might be PH related? I know my pH was too high for a while in the hydroponic system and the cucs seemed really slow off the mark. I have hard water so the ph is kind of a battle.

That could be it - We have a well with pretty hard water. I'll get a Ph kit today and check the Ph level. Is the recommended Ph for cucumbers the same as for tomatoes and peppers? I have them all in the same system.

I have some pictures at the link below

Here is a link that might be useful: Soggy Tomatoes

a PH of 5.5 is recomended for cucumbers. I think Tomatos are recomended 6-6.5 I don't know about peppers. You can probably find a happy medium on the high range for cucs and a little low for the toms that may work for everything. I would probably Aim for just below 6 bassed on what I do know at this time.

I'm starting to wonder about getting nutrients formulated for hard water since the PH tends to swing back up so much. I hate having to add acid every day. I'm actually wondering if using some media that tends to shift the ph to the acid side might actually be good for my situation. Anyway, let us know what your pH is once you test it.

I tested it this morning and it is right on 6.5, so it's great for the tomatoes, but high for the cucumbers. It's odd because just plain water out of the hose is very high - 8.5+. I guess the nutrient solution must have pulled it down. I'll see if I can add a little acid and drop that number down to around 6 and see if that makes a difference.

Actually, the Ph kit is sort of fun, so my 8-year old and I have been running around testing the Ph of everything we can find, from Sprite to lemon juice. I now know the Ph of just about every liquid in my house. I figure with as bad as the science programs are in the public schools that it can't hurt to encourage some of that sort of thing at home so we're treating the hydroponic garden as one great big science project.

hydrotrout,
I like the science project idea. Science and interest in the natural world is so important to learning.

My cucumber plants are getting tall. So far I have a huge fat cucumber and one skinny cucumber growing but the leaves are yellow as well. What can the problem be. Did I possibly spray too much organicide on them?