Planted Tank Guru
Join Date: Feb 2010
Location: Newbury Park, CA
My substrate is Schultz Aquatic Soil, same thing as Turface, and the tank has been set up for nearly 10 years as a heavily planted, CO2 injected high light tank. Maybe 5 years ago the substrate got so full of detritus I couldn't poke my finger through it so I pulled up the plants [wasn't easy], deep vacuumed the whole tank over about 3 days time piling the vacuumed substrate up and doing a couple inches in the python tube at a time until it was mostly clean. After all the substrate was gone through I replanted the tank and did daily water changes vacuuming the surface to get the surface gunk off. There was plenty of organic matter left underneath of course. There were no foul odors of any kind in the tank during my massive clean up, it smelled like good soil throughout. Since then I just do this where I want to do plantings. This is a huge disruption of the biological filtration of the tank and who know what other process and not a good idea.
I get lots of non smelly bubbles coming up from the substrate when lights are on but not when lights are off. All substrate bubbles are not from anaerobic bacteria and to be feared. Light seems to penetrate about an inch into my substrate. All detritus isn't nasty bacteria filled stuff you need to get rid of. It may be bacteria laden but bacteria aren't 'germs' and are an extremely important part of the aquatic ecosystem.
Never have set up a soil substrate but suspect you might get the smelly SO2 going on a recently set up tank as it might develop from too much rotting organic matter before the substrate develops the bio load it needs and new healthy roots.
As a child I had been taught to break down the tank and rinse substrate until it was completely clean. Even back then the year old never vacuumed gravel from an unplanted fish tank didn't smell nasty. Switching to this tank I just moved the dirty substrate, handful by handful, filled the tank, vacuumed the surface and planted. This preserved some of the mulm but not all of it. The sky did not fall down doing this, er - I didn't lose all my fish/get massive algae/dead plants. I was quite amazed.
A fish tank isn't going to consist only of the stuff you put in. It would be a failure if it did. You need a diversity of organisms of all sorts for a successful tank. We know and accept the nitrification bacteria for the biological filter they provide but there are many more involved.