ive got a 30 gallon freshwater tank that has a sand bottom. well its a clean white sand, and basically over time it develops dark spots. (even though i vacuum it frequently)
basically they are too heavy for the siphon to pick up, and if i run a fish net through the sand they are too small and slip through.
are these spots unhealthy for the tank? how can i remove / prevent them?
(also some of the small debris in the sand is broken up driftwood
heres 2 pics to give detail :
basically they are too heavy for the siphon to pick up, and if i run a fish net through the sand they are too small and slip through.
are these spots unhealthy for the tank? how can i remove / prevent them?
(also some of the small debris in the sand is broken up driftwood
heres 2 pics to give detail :
