It's been about 2 weeks? 3 weeks? since we set up the new pond. We were given my aunt's above ground pond set up and her very large goldfish. All the fish seemed to be doing fine until about two days ago when one of the really big comets seemed lethargic. I caught her and examined her...some scales were missing from one side (I assume from spawning and/or from being caught and handled.) It looked like a secondary infection had set in, so I QT'd her and medicated. Within hours...I lost her. Then the next day I found Zebra, a large 6 year old shubunkin floating. There was nothing amiss!! No signs of disease or parasites. But then I am been blessed by a mostly trouble-free pond experience so far. In other words...unless there were obvious signs of disease...I might miss it.
I checked the water with a test kit...nitrites were zero, nitrates zero. I had just cleaned the big pondmaster prefilter and set up a trickle filter with Louisiana irises (they grow happily bareroot in the trickle filter rocks.) Nevertheless, I did a 10% water change.
Today I noticed that two of the other fish were not eating and seeming lethargic.
I called my aunt for some background information. This is the seond time their pond has been completely drained/refilled in less than six months. Both times she said the water was "bad." I didn't press her for exactly what bad meant...but it was in the context of fish being overcrowded, fish dying, etc. She decreased her numbers last time, but this time (when we disassembled the pond) the water was "bad" because two 14 inch plecostemous had not overwintered and had rotted in the pond. I can attest that the water was foul. Even the lilies smelled awful and had to be washed before I put them back in the pond.
I am wondering now If I should repot all the lilies and discard old pots, soil and rocks, in case they are harboring disease.
Also...my aunt had only a prefilter running...no additional biological filter. I think she maintained the water previously, but her health problems have prevented her from doing so recently. But I know at one time she had 40-50 fish in there, including two 18 inch long koi. So, it's not hard to do the math and figure that stress may be a factor here.
Late this afternoon the largest of the fantails was acting poorly. Very lethargic, staying at the surface (but not gasping for air or anything) just kind of moving in slow motion. By evening...I had lost her, too.
Two of the fish had severe swim bladder problems...treated, but with remaining permanant damage. One stays at the bottom all the time...only fluttering up to eat. One would habitually swim upsidedown or appear dead. Today he was the other one that seemed especially off. I went to check the pond a few minutes ago in my nightgown with a flashlight (because I am making myself sick with worry) and I found him dead. I wasn't actually surprised by that...he really stressed during the move.
Help!!!! What am I missing? I have backtracked. The only new things are:
-- the water change (I did one on both ponds and on the aquarium in the house, so I know my dechlor is ok.) I was probably a little heavy handed with the dechlor given the fact that I was paranoid. I was thinking along the lines of toxins, but I guess if it were something toxic that had gotten into the pond, all the fish would probably be affected.
--the trickle filter...but it's just rocks and irises in pots on a plastic shelf. I have used other parts of this shelf in the other pond, so I know it isn't toxic.
--I added plants from my original pond. I know all ponds have their own "bugs" but I have not had sick fish EVER.
--I added a few lily divisions. I took those out tonight and put them back in whiskey barrels...just in case.
Most of the fish appear just fine. They are eating, swimming normally. They are not used to me, so they don't swarm the surface at feeding time. I wish they did. I can tell with one look if one of the fish in the orignal pond is missing or injured or "off." These sort of strike the fish food and dart to the bottom...so it's hard to assess them.
Some stats:
The pond is 11.5 x 8 and 2 feet deep. Currently there are about a dozen goldies. The smallest is a young comet who is about four inches. The rest are 8-12 inches long. The fantails are probably 6-8 inches. The oldest ones are 4-6 years old.
I have lilies, pitsia, elodea and hyacinth...and louisiana irises in the filter. They are planted in the same clay I use for all my other lilies. My aunt had some of that soil-less potting medium for aquatics...I put one division in that, just to see how they would do.
There is a 950 gph pondmaster pump with associated double tray prefilter. I have it attached to a fountain which goes into the trickle filter. It's ugly, but functional temporarily while I construct the biological filter...probably a skippy or an external barrel filter. I know there is no ammonia or anything else containing N in the water. Besides the water test showing zero, the hyacinth and the pitsia are anemic and pale. Everything else ..pH and hardness, etc...all normal. I don't tinker with pH anyway. Neither did my aunt and we are using the same city water source.
Given the abundance of baby fish, it is possible that they may have spawned. (Or the baby fish come from the original pond via the plants. )
I clean the prefilter every couple of days...I kind of freaked out when I saw bloodworms in there...those are ok, right?
What am I missing? I really don't want to lose anymore :'( but I don't see anything I can treat. I examined each fish after they died...their gills all looked dark red...no signs of anything parasitic or caustic. I even checked to make sure they hadn't eaten a rock (I saw that online.) Their slime coats were fine...no signs of trauma or illness anywhere.
I am just sick about this. Any thoughts would be greatly appreciated.