I just wanted to share a disaster I had with an autofeeder, and a Fluval Spec V.
It was one of those very common feeders that has a clear plastic barrel that it rotates and a door drops down and food falls out. The slider that controls the amount of food was loose and apparently dropped down a few notches so over some time it was steadily dropping more food. I do water changes weekly but hadn't noticed the food as the shrimp do a great job of cleaning up the visible mess.
Over time however the food that was swept into the background and into the gravel that was not eaten decomposed. I think this may have taken somewhat longer to become noticeable as I have over-sized the bio filter capacity with mods
, and as it does take time for the amount of food dropping to increase and for food to decompose the bacteria on the bio media had time to ramp up.
Anyone familiar with the original Fluval Spec V filter material will know the amount of bio filter material I modded it for is ridiculously greater than the size of the aquarium should ever have to support. But in the end, I think it saved my tank from certain doom given the way things turned out.
I only really noticed the problem existed because the autofeeder barrel was running low, and the shrimp were really hating the nitrates being generated and running around frantic.
At the peak of the problem I could change the water till nitrate test was light orange, and it would be solid red the next day.
It took 2 days of pretty deep gravel vac that required a lot of plant removal and big water changes to get the nitrates out initially, and for the few days after since the bacteria would be dying back a bit due to less food.
All is well now.