I read on NI that you posted that you found with your bakki shower pond that you get a heterotrophic smell when you didn't add new water for a few days, you found the same with the lava rock. Did you find it more so when you added all the fish (50 fish) from the lava rock pond to the bakki shower pond?

Were you only turning over the shower at 100% per hour rather than the minimum of 150% or recommended 200 to 300%?