Answer: Container grown veggies are notoriously heavy feeders. It is possible that the plants are suffering from a fertility or nutrient deficiency -- I don't believe the fish fertilizer in and of itself would cause yellowing. You might try a top dressing of compost along with using a water soluble fertilizer which contains "minors" in addition to the basic N-P-K. You might also look for a more balanced formula such as 10-10-10 and be sure to apply it according to the label instructions for "active growth". Finally, you might also try increasing the water somewhat now that the plants are so much larger. You need to keep the plants in vigorous growth to keep them producing.
The yellowing might also be a disease or insect problem in its early stages, so look very carefully at the undersides of the leaves and along the stems for signs of anything unusual.
With regard to the size, these plants are about a third the normal size but I am surprised they are vining so dramatically. I suppose it is always possible the tags got switched (if you purchased the plants).
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