Oh yes, fish water, especially dirty, poopy, fish water is great for gardens. I have had gardens since childhood, and also aquariums, and always put the water change water on plants. I use this to water my vegetable seedling starts exclusively until they go outside. I would put it on my vegetable garden outside, but it is too far to carry buckets, so my hostas get it once I put my seedlings in the garden, I can't think of any aquarium chemicals for FRESHWATER aquariums that would be an issue, with the exception of treatments for disease or parasites. I would avoid that tank water for a while.

Dogma is holding firm to the belief that something could neither be a conceptually or practically superior practice because you believe something else seems to be satisfactory - 'works for me'. Old beliefs are like a pair of old shoes - we often value their comfort so much we tend to ignore the fact they're full of holes. Almost everyone prefers the relative comfort of belief to the exercise of reason because believing is easier than reasoning; which brings us full circle to why there are so many more believers than thinkers. My $.02 I'm pretty sure you're not suggesting that a haphazard approach (a little of this and a little of that, even though I know neither what the plant needs nor what I'm giving it) is a superior approach to a well-reasoned supplementation plan. Discounting all reason because we're satisfied with the status quo is self-limiting by default. BTW - if Punky's trees are in pots (don't think that was made clear), moving closer to how nature does things is an exercise fraught with obstacles. Growing in the ground and growing in pots are widely divergent cultures. On a scale of 1-10 with growing in the ground being a 1 and hydroponic growing a 10, conventional container culture is probably a 7 or 8. Al

I have couple freshwater tanks that are setup with high lights, CO2 injection and strict fert program. Since I dose macro and micro nutrients myself I know whats in it. I change 50% of water thats in my 45g weekly so I use it to water everything. From my house plants to everything outside and sometimes even my lawn gets some. You shouldnt have anything to worry about and that water shouldnt be high in nitrogen at all. There is nitrogen present I'm sure but if the fish are alive then its not as high as you think. Most fish tanks run with Nitrate(NO3) Here is a link that might be useful: My garden

In short, yes. Rainwater or melted snow is excellent for orchids, but if you have an area which is prone to acid rain, a ph test might be in order. Also, if you have a new roof, collecting water which has run off the roof may not be a good idea to use on orchids as you may pick up chemicals from the roof. Collecting a large amount of rain water can be achieved by placing a tarp or plastic sheet out in an open area and rigging it in such a way to drain into a bucket or other container. Water collected from dehumidifiers and air conditioning units is fine to use for orchids as it is the same as distilled water, however it does have dust etc. in it. Fine to use on orchids, don't use it on your contacts. Water from aquariums is also used by several growers on the forum to good effect. The water has fertilizer in it already! I would remind people who are using this, however, to NOT use it if you have treated your fish with medications recently...some treatments contain copper and other elements which may be in too high a concentration for some orchids.