Help - Losing Fish One By One.

[jasmas]

Have had fish for 3 weeks now. 9 days ago I noticed an albino was not eating with the others and fat looking, set up hospital tank and treated with eSHa 2000 (all we could get) Next day Demasoni also moved. The albino was bloated, demasoni not so. Albino survived and the Demasoni did not.
 
Albino moved back to main tank after 3-4 days after treatment finished and doing well.
 
6 days after seeing the albino was sick. A demasoni is dead in the tank, also a yellow lab looking very sluggish. That was Wednesday, today (sat) a demasoni is near the surface and a little fat. Moved to hospital tank, also managed to net the yellow lab who was sitting at bottom if tank gasping.
 
Both being treated now with Octozin. 
 
All readings are good apart from KH. Ammonia & Nitrite 0, Nitrate gets to about 20-30 before 50% weekly water change. KH is 6 tho' pH 8.1 and GH8.
 
I'm tempted to increase KH with bicarb soda? But I've been advised to leave it, so it's constant for the fish.
 
What's killing the fish?  All look good but are dropping one by one!
 
 

 

[TwoTankAmin]

First off let me correct a misperception many folks have. Fish have no specific KH requirement. Fish are sensitive to conductivity/TDS moreso than other parameters. GH and KH both contribute to conductivity/TDS as well as a number of other things (think ions, organics, salts). GH has a greater effect than KH in this respect. Your water params are pretty much OK for malawi cichlids. The KH is a tad low but this is only a worry if the pH will not remain stable as this is the primary role for KH. The GH is close to the lower limit suggest for Malawis. You can probably deal with any issues here simply by what substrate you use or how you constitute your rift lake buffer/cichlid salt if you use such a mix. Your pH is fine but both the KH and GH are right on the edge of the lower limits.
 
However, water parameters tend to follow patterns. Higher GH and KH is associated with higher pH. Also it is difficult to change any one of these three things without also affecting the other two.
 

 
Note: GH, KH and pH form the Bermuda's Triangle of water chemistry. Although the three properties are distinct, they all interact with each other to varying degrees, making it difficult to adjust one without impacting the other. That is one reason why beginning aquarists are advised NOT to tamper with these parameters unless absolutely necessary.

from http/fins.actwin.com/mirror/begin-chem.html
 
I do not believe the loss of fish is due to your water parameters.
 
As for what is killing fish. it could be any number of things. But my first question is most tanks normally take over 3 weeks to cycle, so I am wondering how you cycled cycle tank.
 
Next, I am wondering what you are feeding the fish. They need a diet high in veggies/algae and they do not do well on a diet high in meaty foods like blood worms etc.

 
It will accept most foods offered but vegetable matter in the form of spirulina flakes, blanched spinach, nori etc. should form a large proportion of the diet. This can be supplemented with live and frozen varieties. Never feed beefheart or any other red meat as it will interfere with the digestive system of these fish.

from http/www.seriouslyfish.com/species/pseudotropheus-demasoni/
 
I would also suggest before you look to changing your parameters, that you have a read here: http/www.cichlid-forum.com/articles/malawi_bloat.php
 
Finally, none of the above would eliminate the potential that the fish may have arrived in your tank with other problems unrelated to your tank. Fish keepers have a tough time trying to diagnose many diseases/parasites in fish because we can  not see any symptoms and we lack the lab tools needed to determine these things are present. So a lot of the time we simply make our best guess and then treat for that. This is a real hit or miss approach. However, with Malawi fish, I would look to the above mentioned factors first.
 
I should mention that I do not keep African rifties. My water is soft and neutral pH. However, I have a fair amount of experience altering water paramters (in both directions) to simulate dry and rainy seasons and have altered my tap parameters significanly to house acid water fish. This is much harder to do that increasing them for rift lake fish.

 

[jasmas]

Thanks for the reply. Tank was cycled as directed on this website with the introduction of Ammonia, it took just under 6 weeks. We have good filtration (fx6 and internal).
 
Feeding them fine granules twice a day, granules were provided with the fish by the online supplier. Occasionally also feed them with peas cut up fine about once a week.
 
The sick demasoni is in hospital tank, lost the yellow lab yesterday.
 
All fish in main tank seem fine and all feeding, tho' today is water change day when we don't feed them.

 

[gmc1]

Hope you get to the bottom of this.Very frustrating after your hard work.

 

[TwoTankAmin]

I will assume the granules are properly formulated for the fish. That would leave the most likely answer as being the fish came in with whatever got them. My first thought is internal parasites and/or worms. I am not sure about what meds you can get over there but if you can get metronidazole or a medicated food which contains it, I would try that. Metro is a pretty benign med which won't harm filters and an overdose will not kill them either. But dosing at suggested levels is always the best route. You may have better luck finding it in the UK if you search for "Fishzole"
 
If you can find the med and not the food, you can make your own medicated food. Metro is best fed as opposed to dosing the water, but both can be done. If feeding, only feed the treated food and nothing else. Feed twice a day for a week.

 

[jasmas]

OK I got fishzole (metronidazole) needed to get it from the US. It's in tablet form. We've lost a few more fish (((.
 
Now I've managed to move 4 who are not eating and quiet to the hospital tank so will treat that will the tablets as directed in to the water. 
 
Those that are in the main tank and all looking good, I'm planning to feed with treated food. Going check online how best to do that.

 

[jasmas]

Did as planned. alls good, three of the four moved back to main tank, and have settled in well. The fourth was still not eating. I now feel like a fool as she was holding, and yesterday released fry and today been moved back to the main tank, as the fry were away from her, there's about 20 maybe. 
 
Now I've noticed another fish holding in the main tank.