Join Date: Jul 2012
Location: Northern BC, Canada
Most dont wash it from what I've read. Diana Walstad's book recommends just dumping it in and going from there. But you cant add fish right away due to the ammonia spike from fresh miracle gro. Some people say you should let the soil dry out completely first before adding it, as this lets some of the ammonia... I dont know, evaporate? It makes some of the ammonia dissapear somehow.
I washed mine though. Using the mineralized topsoil method. (I was reading so much nonstop about mts and natural planted tanks and got confused about which was which, and was a month into it before I realized I started with the wrong soil type.) I let it soak for a few days, scooped off the floaties, then let it dry out for a few days. I repeated this three times. Then I screened out the big chunks of wood. Mixed in some clay powder, wetted it with water from a dirty filter and mixed in a bunch of mulm from an established tank. Topped with fluorite black sand.
My results were fantastic. No issues with clouding, or the water being yellow, no ammonia spikes during the first weeks, no fungus on the soil cap, nothing ever floating up from the soil even if I move things and replant. My plants exploded to the point were 2 months ago I had 2 small bunches of hairgrass, 3 swords, and 2 bunchs of water wistera, and today I just had to cut and throw out huge handfulls of plant matter just so my fish have some room to swim.
I think I went overboard, but Im really happy with the results regardless.