Fish Mortality

[ozzydom]

We have been having a problem with fish mortality over the last few weeks, it is usually the larger specimens which are dying.

It is only a few fish per pond every day but when margins are so tight it makes a big difference.

After talks with the Fisheries Dept and several other large producers it appears that the problem is widespread.

The Fisheries centre at Udon Thani has not been spared and tests have found a parasite is the cause of the deaths . This parasite has become a nuisance because of bad water quality due to the unseasonal low rainfall , Prajak Lake in Udon is a source as well as many of the small klongs that we draw our water for replacement from.

Fisheries has informed us that the addition of salt to our ponds is about the only treatment available to us.

I am posting this as an information bulletin in case other members are having a similar problem .

The treatment is 100kg of farm salt per rai of pond , dosage should be applied in three stages of 1/3 dose at one week intervals , but if the problem improves after say two doses I would cease then as we have done.

This is just as a safe guard in case the full recommended dose causes problems worse than that already being encountered .

The addition of the salt may also help clarify the pond water and should not cause a problem with commercial freshwater fish and crustaceans.

[slapout]

Ozzy; the addition of salt water will clear the water. I have never used farm salt as we has salt water avaliable (from producing oil wells). We use to pump about 200 bbl of salt water into a 1 to 1.5 acre pond to clear it up after rainey season run off (positive/negative charges of particles, would knock solids out for a clear pond) I would wonder if mixing the salt in water and then spraying on the surface of the pond is how you did it or did you just spread the salt crystals by hand?

[ozzydom]

Ozzy; the addition of salt water will clear the water. I have never used farm salt as we has salt water avaliable (from producing oil wells). We use to pump about 200 bbl of salt water into a 1 to 1.5 acre pond to clear it up after rainey season run off (positive/negative charges of particles, would knock solids out for a clear pond) I would wonder if mixing the salt in water and then spraying on the surface of the pond is how you did it or did you just spread the salt crystals by hand?

I started off by putting 10 kg in mesh bags but the rock salt dissolved quicker than I was led to believe it would so I ended up throwing the stuff over the surface to get a better coverage.

Seems to be working ,deaths this morning ,nil,.

[Lickey]

Brother in UK puts a pinch of table salt in his aquarium every now and then, he says it neuatralises ecess nutrients in the tap water when he changes the water, So perhaps the low rainfall in your area isnt dilluting agri run-off enough?

Tell you what Dom, there has been so much rain here that an old well at the bottom of the farm [15mtrs deep] is spewing out water now,and if the rain carries on, it will come out of the top of the borehole soon! so no worries about water in the dry season.

Quick question for all, at the village lake about 8rai, with a buddha temple in the middle, its full of huge goldfish and others i dont know, there are no visible water plants, the sides are all concrete/stone, the only water feed is rainwater and run-off from the streets, Mrs says there is no caretaker and all the fish eat are those 5bht bags of pellets, smell a bit like Winalot dog food, anybody know whats in these pellets?

Will try to get some pics of the fish and lake next time the sun shines!

Cheers, Lickey..

[Lickey]

As promised Dom, here are some of the fish in the town lake, it hasnt rained for 3 days now,

No idea what names the fish are, Pan reels off the names but i would forget my nuts if they wernt in a bag!!

Come and have a look yourself, they are bloody big! Cheers, Lickey.

[Smithson]

Any news on the fish death front? Was it mainly Tilipia or other varieties also?