Seems like you are in good hands, but I wanted to throw a few things in the mix as possibilities.
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1) Pull the roots/soil out of the pot and make sure the bottom roots aren't suffocating/rotting. Check that they are a healthy whitish color. If not, then the soil may not be drying enough on the bottom half. I get this with plastic pots often.
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2) Have you tried spraying with water/epson salt? Sometimes the magnesium helps.Â
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3) If there is no root rot or drying problems, I would flush the soil with clear water, let it dry over the next few days, then start over again with fertilizer.
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But since you answered ajdrew's question about the growth and you stated they are still growing, chances are the roots are fine. But it's good to check.
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Oh, and MarianneW's question may help you out too. If your ph is off, it could render a plant that looks like that.