Baby discus dying off one after the other

Absolutely frustrated I will try to summarise quickly:

Purchased a breeding pair + 17 (3-4 week old) babies about 20 days ago.
Pair went into big tank, babies in small 54L tank.
All babies looked well and fed eagerly on beef heart mix and brine shrimp. Since I work all day i was feeding them a couple of times in the morning, and then multiple times in the evening (adding tiny bits at a time until i noticed they were done) so they were being fed from about 6 pm to 11pm, and in weekends and holidays I was able to spread throughout the day. Before going to work they get a 30-50% water change as I syphon leftovers. WC is done with tap water at tank temperature (31-32 celsius) and treated with PRIME before going to the tank. A second WC same as above before going to sleep.
Tank had an external filter (sponge covered intake) and sponge air driven filter.
Found one baby dead about a week ago, didn't think too much of it since other looked perfectly healthy and active etc.. Second one dead next day... Check water, i see nitrites: panic, and chug them all (acclimatised through a drip) in the big tank with the bigger adult Discus (at temp 31C). Within 2 days i lose 3 in the big tank. In the meantime I sorted my nitrite problem (wrong setup of media corrected in external filter + add Polyfilter recommended by LFS ). So i bring them back to the 54L tank on their own. And i keep on losing one every 12 hours. From 17 I am down to 5...
Temp had dropped to 29C yesterday so i replaced the heater and they are at 31C - they were no longer eagerly feeding and have been shy the last 2-3 days.
last test: PH 7.4 or less (I find the scale hard to read), ammonia 0 nitrite 0 nitrates 20ppm prior to WC KH 3 GH 5
Any ideas?

There are, as with so many cases, many different reasons.

Including:
Maybe the babies were too young when moved.....but that cannot be tested.

Food for the babies......has it been goods enough?

Moving them from their parents........was it done properly?

Water chemistry....Immediate effects and lasting effects.
Some effects of wrong water chemistry cause lasting damage.......a single incidence of hight nitrate, for example, can damage the gills for ever. High values for other water parameters (even if only transient) can cause lasting damage that can either compromise the fish' health or kill it some time after the event.
Baby fish are particularly susceptible to bad water.

Really, for young discus that are in trouble you need conductivity readings.

Uneaten food.....causing nitrogenous waste spikes or spikes in chemicals not tested for or increasing microbial growth (and some microbes will produce toxins that will rapidly kill the fish......adults can die within minutes, and fry stand no chance)

Health....
Velvet disease.....has it been checked for?
Other parasites?

The list goes on with guesses without any other information to go on.

ps.....just noticed you use Prime.......that requires an increase in aeration.
It should never be used to decrease ammonia; ammonia should be decreased by a more persistent method.
ian

Hi miamiheat
Sorry to hear about the babies i know you love your discuss.
I used to kill all my fishes until someone on the forum pointed out to me that by using my hot tap water i was adding copper everytime until the concentration was high enough to kill them ( the hot water comes fom a copper tank ).
Regards
Anthony

Thank you Ian i have written a long answer and bug/glitch it never got posted.
I was worried because my last 5 were very shy suddenly and did not seem to eat, but tonight they are acting normal. We'll see..

Thanks Anthony, i have been using warm water therefore yes I have been using the hot water tank. But i think I would have killed all my fish by now if this was the case since I have been doing this for over 3 months. Am I wrong in making that assumption?

Hi Stephan

It looks like you have been having an awful time.

I think it would be better if you heated the water in a bin rather than hot water from a tap.... Also how about adding
a few plants in pots or floating ones so that you have some biological filtration going?

Another suitable addition could be a type of Mattenfilter used by discus breeders in Germany so your barebottom tank wont be as prone to spikes.
www.janrigter.nl/mattenfilter/

Some useful links in that article.

All the best

Abe

anthonyd wrote:

Hi miamiheat
Sorry to hear about the babies i know you love your discuss.
I used to kill all my fishes until someone on the forum pointed out to me that by using my hot tap water i was adding copper everytime until the concentration was high enough to kill them ( the hot water comes fom a copper tank ).
Regards
Anthony

Another one dead wednesday night.. Down to 4... Sounds like a countdown..
Just to be safe i started filling a bucket with cold water and brought it to temperature using heaters and I added and air stone in there (i treated with prime). We'll see what happens.

why have you got the temp so high ?
drop the temp to 28. its too high at 32 and also that will affect your oxygen levels
also, if you were filling the tank with water from the hot tap, thats a big no no.
only use the mains fed tap(usually you kitchen sink)

Damian_Ireland wrote:

why have you got the temp so high ?
drop the temp to 28. its too high at 32 and also that will affect your oxygen levels
also, if you were filling the tank with water from the hot tap, thats a big no no.
only use the mains fed tap(usually you kitchen sink)

Hi,
I have been told by the seller who breeds them, and by a couple of other breeders, that 31C is the temperature they should be kept at at that age. We are talking about fish that is 2-3cm.
As far as hot tap water yes I agree I started switching to cold water that will be brought to temperature via heater.

Stephan hope they stop dying .

When I have to add water after a WC I always heat one kettle and add it to the bucket, and then I add the treatment for chloride, etc..