Brassavola nodosa, Dendrobium aberrans. New here.. feedback on setup please!
 

Hi! I'm relatively new to growing orchids and I would love some feedback/pointers from others! I have a mounted Brassavola nodosa and Dendrobium aberrans over an aquarium. I have some horticultural charcoal between the wood and the roots ( I can't remember the types of driftwood I mounted on) and then some spagnum moss near/ around the roots. I pour water over them about every other day. I spray them about once a week with the Miracle-Gro orchid spray, sometimes I water them with the aquarium water as well. There is a south facing window about 5 feet away and they seems to be doing well, but I have a soltech aspect pendant light coming in the mail this week. The humidifier is always going and the ceiling fan is always on high. The Brassavola is thriving and growing quickly, but the Dendrobium is growing slowly in comparison. Looking forward to hearing your feedback/suggestions!

Welcome to the Orchid Board!

Those two plants have very different light and water requirements. The Brassavola needs extremely bright light to flower well. Where do you live? It might be happier outside in summer. It doesn't need any moss around the roots when mounted. In fact, many people grow them bare root, dangling from a wire. Water when completely dry. It is fine to water every day or two if they dry that fast.

The Den. is in Section Latouria. They generally prefer being evenly warm and moist all year, in bright shade. It is better if they never dry completely. I wouldn't try growing one mounted except in a humid greenhouse, unless you can ensure it doesn't go dry for long. They go downhill rapidly if not watered enough. Bright shade is fine. Your light will probably be enough for it.

nodosa is 2500-3500fc
aberans is 2000-3000fc

So both can easily be cultivated under 3000fc strength of light.

The dendrobium is growing slow because it is getting too little light. It hasn't got as many roots as the nodosa so can't store as much water, you also have more moss around the nodosa.

This means the aberans needs to be watered more than the nodosa. At least until it has grown more roots.

You can try experimenting with more moss for the aberans so it can hold moisture for longer but don't use too much that is stays too wet.

Aim for moss to increase humidity around the roots but not to cover roots completely to smother them if that makes sense (more needed underneath the roots)

Dendrobiums are quite slow to adapt to a new environment. Just make sure it keeps growing. Look for signs of new root growth once it is receiving enough light.