Dwarf cichlid deaths

Question
Hi Ron

I've asked you about this before but now have some more specific info.  
Would you mind taking a look and letting me know what you think?

I can't seem to keep dwarf cichilds.  I have had several deaths over the past
year and the pattern is always the same: I buy a pair, they breed very quickly
once or twice, and then within two months or so they succumb to fatal pop-
eye or dropsy, with one fish dying at a time.  Most recently I lost an M.
ramirezi to dropsy.  Due to flashing and yawning I treated with Sterazin (anti-
flukes), but when I returned from a short holiday she had bloated and was
dead within a few days.  I am currently treating with Interpet's Anti-internal
bacterial infection treatment, as I have an M. altispinosus who I am worried
about.

The symptoms go as follows: the fish will start behaving oddly, darting and
flashing with subdued colouration - then they will seem to recover and
behave normally for a couple of weeks, and then suddenly pop-eye or
dropsy.  Most recently - and I think this might be key - I have noticed a very
specific sympton - and that is that their eyes (possibly only one but I can't
verify this) seem to be irritated.  Before she died the M. ramirezi would use
her pectoral fins to rub at her eyes, would stretch her head from side to side
and then very carefully try to rub the eye on the substrate.  But there was
never any visible signs of damage or parasites to her eye.  The M. altispinosus
is now doing the same eye-rubbing - with fin and on the sand - and I cannot
see any thing on his huge eyes!

You suggested using Clout but that is unavailable in the UK, and I do not
think it is a parasite.  I have tightened up maintenance by changing my
bucket to a food standard one and making sure that the tank is now free of
detritus.  I believe water conditions to be perfect: readings of ammonia and
nitrite are consistently zero, pH is stable at 7.4 (despite CO2 being added),
and nitrates are very low due to using an RO/tapwater 80/20 blend for weekly
30% water changes, which I add cold, but only drops the tank temperature by
a degree.  The cardinal tetras who have always been resident are healthy and
growing strongly.  I feel I am doing everything right and yet I have these
heartbreaking deaths - please help!

Many thanks

Yours

Joe

Answer
Hi Joe,
 I'm very sorry for the delay in answering.  Unfortunately I really don't have anything to add.  It is very strange that they are rubbing their eyes and even stranger that the cardinal tetras are still alive because normally they would be long dead before a cichlid would even think about dying.   I assume that you do not have any peculiar ornaments in the tank made out of metal or something like that or some local rock that is slowly dissolving (e.g., shale or something with sulphur in it)??  

It certainly is a peculiar situation.

-- Ron
  rcoleman@cichlidresearch.com
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