02-10-2012, 06:38 AM
Koi are best in fairly neutral - slightly basic (7.0-8.0 pH) water, but quick swings even in that range can wack them for a loop...
I would doubt that the water got them...as the fish disappeared - bad water usually makes floaters & sinkers.
If the spot is indented, most likely a bite or scrape, if it is raised, might be a bump or infection/reaction.
BTW: A good sized heron can down a nice quantity of small fish...esp if it hasn't eaten in a few days...look for their nice sized footprints along the edge -they can hunt with one foot tucked up...so may only find one footprint
I would doubt that the water got them...as the fish disappeared - bad water usually makes floaters & sinkers.
If the spot is indented, most likely a bite or scrape, if it is raised, might be a bump or infection/reaction.
BTW: A good sized heron can down a nice quantity of small fish...esp if it hasn't eaten in a few days...look for their nice sized footprints along the edge -they can hunt with one foot tucked up...so may only find one footprint