Trouble with dirted tank
I recently moved to a new house, tore down my low-tech 40 breeder, and decided that it would be nice to try dirt with a BDBS cap when setting it back up. Its been almost 2 months since I redid the tank, and I have been having so much trouble with the dirt that I'm thinking about tearing the tank down again.
I used around an inch of soaked Miracle Grow Performance Organics Container Mix in the tank (as this was the lowest nutrient mix I could find in my area). Before adding it to the tank, I let it soak in a Rubbermaid tub for about a week and a half to leach off most of the ammonia and to remove most of the larger barks chunks, peat moss, and perlite. I capped the dirt with 1"+ of medium grit BDBS (closer to 2" in most areas).
Since set up, the tank has been a constant mess. Water parameters are good (0-0-<5 ammonia-nitrite-nitrate) and plant growth has been decent, but the dirt is breaching the cap everywhere. I vacuum the top of the substrate lightly during water changes (30%, 1-2x per week), but typically 1-2 days later, so much dirt has come up through the cap that my plants are covered in it and there are piles on top of the sand. I am also having to clean my canister filter once every two weeks so it doesn't become clogged with dirt. I have been really careful not to uproot plants or disturb the cap during water changes. I have also added additional sand to cap major problem areas (up to 3" in some places), but this still isn't helping.
Is there anyway to fix this without scrapping the tank and starting over? Where did I go wrong here? Should I go back to BDBS alone and be satisfied with less-than-great plant growth?