17th March 2013 at 2:34 pm #830
The nail or (any steel) in the sand will react with the O2 in the water, converting it to Iron Oxide. The O2 will not be available for the microbes, killing the biofilter.
The nail or (any steel) in the sand will react with the O2 in the water, converting it to Iron Oxide. The O2 will not be available for the microbes, killing the biofilter.