fish dying one every few weeks

[betcher n0t]

1~What type of fish is afflicted? In addition, please describe what is wrong with the fish to the beset of your ability (i.e. cotton like growth, bloated, etc.).

Fish range over a number of species - kuhlii loaches, bristlenose cats, rainbow cichlids, convict cichlids, upside down cats. No symptoms noticeable

2~What are your tank parameters (ammonia, nitrites, nitrates, temp, pH)? Please give exact values.

all params just before water change: amonia 0, nitrite 0, nitrate 5ppm, gh 80 ppm, kh 50 ppm, ph 7.6 - 7.8, P04 5 ppm, Fe chelated 0, Fe non chel 0, calcium 40.

note my tap water is around ph 7.6, gh 60 - 80 ppm, kh 50 - 50 ppm rested for 24 hours to let C02 to equalize.

3~ How large is the tank? How long has the tank been set up?

4ft . with the sump about 210 litres. Tank has been set up most of this year but has always been sick.

4~What type of filtration are you using? Please give the name and number (i.e. Fluval 304) and amount of gph if known.

home built sump filter with plenty of capacity. I am running peat moss recently in the mechanical filter with filter wool.

5~How many fish are in the tank? What kinds of fish are they and what are there current sizes?

currently there are three rainbow cichlids about 2" two convicts about 1 ", three bristlenoses ranging from 0.5 inch to 3 inches, five kuhliis ranging from 2 inches to three inches.

6~When is the last time you did a water change and vacuum the gravel? How often do you do this? How much water do you remove at a time?

I water change every 1 to 2 weeks and have been vacuuming the gravel each change. Water changes in the order of 50 litres

7~How long have you had the fish? If the fish is new, how did you acclimate it/them?

range from two weeks to 6-8 months

On addition I float for 2 hours adding a quarter to half a cup of water every half hour

8~Have you added anything new to the tank--decor, new dechlorinator, new substrate, etc.?

peatmoss, sodium bicarb

I have had a bad run. I assumed that I initially got a bad batch of fish. Then I lost some due to some agressive fish. I then invested in some more test kits and have been monitoring water quality. Only changes have been to add peatmoss to reduce GH and sodium bicarb to increase kh and ph stability. I had thought that the problem was stress from ph fluctuations at water changes.[/quote]

thanks in advance....

 

[mattrox]

hmmmm Peat moss also lowers pH and Bicarb raises it. I think the bicarb may have little effect being used in conjunction with the peat, except to add sodium to the water. It sounds like you recently started using these and are probably not the root cause.

Were the fish eating before they died? It does not sound like a cycling problem, unless the new fish considerably added to the bio-load... but doubt it.

Have you taken a dead fish for an autopsy? If there are no obvious symptoms you may need to find a vet experienced with fish...... they are hard to find up here (Darwin). If you can identify if the fish have flukes, tapeworm, intestinal paracites then you could treat the whole tank.

What does everyone else think?

 

[TankGirl]

I have heard of hexamitosis causing this kind of thing, with no outward symptoms, just fish losses. I'd treat with Hexamit in the absence of any other obvious signs.

Do you dose CO2 or other ferts? Excessive CO2 could do it, but it would really affect all of the fish - that's why I'm really thinking a disease.

It is wise to increase KH for pH stability, but it does not look like there is very much difference in pH between tap and tank.

Kudos to you for answering the questions from the sticky - it really helps a lot and saves time

 

[betcher n0t]

hmmmm Peat moss also lowers pH and Bicarb raises it. I think the bicarb may have little effect being used in conjunction with the peat, except to add sodium to the water. It sounds like you recently started using these and are probably not the root cause.

Were the fish eating before they died? It does not sound like a cycling problem, unless the new fish considerably added to the bio-load... but doubt it.

Have you taken a dead fish for an autopsy? If there are no obvious symptoms you may need to find a vet experienced with fish...... they are hard to find up here (Darwin). If you can identify if the fish have flukes, tapeworm, intestinal paracites then you could treat the whole tank.

What does everyone else think?

One of the struggles is that there have been a number of possible causes and it is so long winded you never know if it is fixed. about two months ago I came to the conclusion that perhaps it was stress due to water parameter changes because at that stage the water was high gh - 160, low kh and evidence of ph fluctuation. I decided to try and bring the water in line with the tap which I have done for a number of weeks now. PH is a little high on what I would like. One worry for the future is whether after the bush fires the water params are up the creek.

I had thought of culturing some slides to check for parasites and should probably be the next on my list.

 

[betcher n0t]

I am not using any C02 but am considering it as it is difficult to maintain kh with ph already high. No fertilizers, plants going wild anyway probably from the phosphate and good light. Kh was around 10 before I adjusted it. Now I am watching it closely to keep it in line with the tap water.

I will check into the hexamit.

Cheers Paul

 

[TankGirl]

Make sure your KH is 3-4 degrees before injecting CO2, or your pH will indeed be subject to swings.

A culture for parasites or a necropsy would likely be telling, as Mattrox suggested, if you have the ability to get these done.