A fish died...

[Litzi1964]

Brief background: I installed my pond late last summer. It is about 7 ft by 8 ft by 1.5 ft deep with a pvc liner. Re filtration and aeration, I have a combined pump-filter box unit that moves 325 gph. I also have a skimmer and canister filter attached to a 1200 gph pump, and yesterday I added a 325 gph pump with a fountain. My fish wintered outside without incident. I did a "spring cleaning", removing dead leaves and debris and a 50% water change in early April. And yes, I used dechlorinator. Before my spring cleaning I had a large algae bloom. With the cleaning I did use an algicide. I also added Simply Clear. April 18-19 we had flooding which left my water opaque brown, so I did another cleaning and 50% water change. After the water cleared a few days later, I added 2 new fish that had been in a quarantine tank inside. All my fish are comets. I had a total of 8, who ranged in size between 1-2 inches. I got a huge algae bloom, so I cleaned the pond yesterday and added the fountain. I did NOT do a water change. This morning one of my "established" fish (who wintered there) was dead. I looked at her closely and I saw no obvious signs of illness or injury. She DID however look very pregnant, and my fish have been engaging in courtship behavior.

Any ideas?

 

[capewind]

First off, WELCOME

Too many things going on for me to give a good GUESS at what went wrong, but I do have to ask what your water temp and air temps were at the beginning of April. That is a massive water change/iffy time of year to be pulling out/stirring up muck, and I know it was still pretty dang cold here. Unlike Koi, comets are pretty hard to kill. Is it possible for a female to die from being egg bound, sure, but normally, they'll just reasorb them if no spawning, and again, back to cool weather ...

 

[Litzi1964]

Capewind, thank you. When I did the spring cleaning, our high temp was 67. The water temp was in the low 50s. We did have some rather volatile weather. We had a 21 degree air temp drop from April 9-10, from a high of 63 to a high of 42. We had another huge jump from April 13-14, with the high going from 45 to 72. The flooding and heavy rain coincided with another big shift on April 18-19. The high dropped from 63 to 38. From April 28-30 the high jumped from 66 to 84. By May 3 the high dropped to 52 and the next day the high was 73 and it has stayed warm. This was also a fish I'd had for several months, outside.

 

[Waterbug]

I've certainly had female goldfish beaten to death when spawning. But normally there are some missing scales.

A single fish dying could be so many things the speculation would consume volumes. Without a lot of lab work there aren't even any clues. Every item listed, water changes, algae, etc., could all have dozens of deadly theories attached to them and then you have all the possible combinations.We're talking about billions of possibilities. And we're only talking about the possible problems you're aware of and not the hundreds of other possible problems you're unaware of. That could put us into the trillions.

My point is why spend time guessing? It really does no good and can lead to real harm if you talk yourself into something that leads to "cures" that kill fish. Instead if you use the time to research better ways to keep better water quality, dangerous of screwing with fish when water temp is below 65F, benefits of testing things like ammonia and dangers of ammonia, pH buffering, benefits of adding cover and spawn mops during spawns, etc., your fish will have a much better chance overall imo. Given a good environment and good food the fish can normally handle problems.

I'm impressed by overwintering fish in a 1.5' deep pond in IL. Talk about tough fish.

 

[Litzi1964]

Before I did spring cleaning, I did test the water. The ammonia level was slightly elevated. Everything else--pH, nitrates/nitrites, chlorine, hardness was ok. I was starting to get some algae, and I wanted to clear out the winter debris to avoid nitrate/nitrite, low o2, and ammonia problems. They also forecasted several days of warm weather, and i was afraid if I let it go until the following weekend I'd have a real mess on my hands, and possibly some dead fish. After the cleaning I installed netting over the pond so this should avoid an accumulation of leaf debris. And about a week ago I put my plants back in.

 

[Litzi1964]

An update--I did a water test last night and it was perfect. Ammonia, nitrate, nitrite and chlorine were at zero. The ph was neutral and the water was between soft and hard. Water temp was 68. Algae under control. The only thing I'm concerned about is I haven't seen one of my new fish for a couple of days. The pond is covered with net so i don't think a predator could have gotten her.

 

[Dave 54]

Waterbug is indeed part way correct in what he says.
A wise old koi keeper once said become a keeper of water before a keeper of koi and that is as true today as its always been .
From the sounds of it your flood was the start of your problems something somewhere isnt rght with your pond and we need to find it ASAP so to speak. .
If the rest of the fish havent been seen by you for days it may indicate they are sat of the bottom most probably clamped against something or other maybe even the huge 50% waterchange you did.has upset the delicate ballence of these fish.
When you did your water change did you also do your filter at the same time ?
For future reference we start our spring cleaning operations the second to the last week of May by cleaning first the second and then the third filters .
Its the same for the last two weeks in August we completely clean and then re-seed them prior to going into winter,do you haveany winter detritus i the pond i;e rotting leaves etc ?
I'm wondering what was the temperature varient prior to you doing the spring clean as upposed to the water temperature and that perhaps you have introduced thermal shock into your fish it being the reson for their non appearance.

rgrds

Dave.