Problem Pleurothallis

[anramitaco]

I have a Pleurothallis eumecocaulon, which is one of my favorite plants. I've had it for several months, during which it bloomed nonstop. Now it has been putting up new leaves, but the problem is that as the new growth matures it remains much smaller than the old growth. The ramicauls on the old growth are about four inches long, but the recent ones have been only 2-3 inches long. The leaves are noticeably smaller, too.

The plant is on a grow-rack in front of a large SSW-facing window, with supplementary CFLs. It is shaded from both the sun and the CFLs by other plants (nepenthes) and receives indirect light, perhaps a little dappled sun in the late afternoon. I water with distilled H20 and never let it dry out. It gets half-strength orchid fert (Better-Gro) about once per week, when I remember. The humidity is between 50% and 70%, depending on the day. Temps range from 68-70 (night) to 80-84 (day). Lepanthes calodictyon, P. alata and Masdevallia erinacea are all growing in much the same conditions and do not have this problem.

Any ideas? This is by far my favorite orchid and I would hate to lose it.