Greetings,
I am new to the ponding hobby and I am in need of assistance. I built a 300 gallon pond last summer and made a small 10 gallon biofilter for it. It stayed clear through the winter then the whole pond and filter became overwhelmed with "pea soup". The goldfish started dying one by one about every other day. I recently completed a new 90 gallon filter made up of 3 30 gallon filter stages. The first stage is downflow through lava rock, the second stage is upflow through lava rock, and the last stage is downflow through PVC ribbon. This filter has been running for a week and the water is pretty clear down to about 2/3 of the 30 inch depth. I came home today and found a small and a large fish dead. I checked the Nitrate, Nitrite, Ammonia, PH, Hardness with test strips from Walmart. They all appeared to be in the safe zone, although the PH was on the high side, but still safe. I have had the return line from the last filter stage flowing back into the pond from a 12 inch drop, causing plenty of air bubbles. I thought I had everything covered, is there something I'm missing? I have alot of money in the pond and the fish and I hate to see them die.
Please help!!!!
