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Rob321
02-22-2010, 08:12 AM
After a 15 years hiatus from keeping discus, or keeping any other fishes, I knew it was time to get back in the act the moment I stepped into my LFS and spotted a breeding pair of snakeskin discus, which were attentively caring for 33 fry. I was instantly captivated by the harmony exhibited by the pair as they gently passed their young brood between one another to graze. During previous visits to this store I had noticed several other beautiful breeding pairs for sale, however I had never actually seen any of these pairs exhibiting the tell tale pre-spawning body language of bowing and shimmying, let alone knowing for sure that they were fertile and cooperative during rearing.

So when I saw the little snakeskin family group in the store tank, which had effectively cleared all the discus spawning/rearing hurdles, the significance was not lost on me. I thought to myself, “This is just too good to pass up,” and I immediately purchased the lot. That was back in November 2009.

Sadly, I lost all the babies about two weeks after bringing them home due to my inexperience with respect to the property of delayed pH rebound that was happening in the tank few hours after buffering my mains water. I used Discus Buffer in a bucket of tap water to reduce the pH from 7.9 down to pH 7.0 (LFS parameter), but then it would jump back up to about pH 7.6 in my tank. Luckily the adults didn’t suffer much from these fluctuations. Oh well, live and learn. Regardless I switched to buffering with Proper pH 6.5 for my mains water in an aerated bucket for several hours until the pH becomes stabilized before I mix it with distilled/RO water, and then finally add it to my tank.

Within several days of the fry’s absence from the aquarium I was happy to see that the pair spawned. However, all the eggs turned white with fungus. I had been using a mix of 50:50 tap water to RO, which is what the LFS told me they had been using for the pair. My tap water hardness is about GH 170 ppm and KH 120 ppm, so the aquarium water ended up with a GH of ~ 85 ppm and KH ~60 pmm. After a couple more unsuccessful spawns I realized that those values are still too high for proper fertilization to occur. I then switched to a mixture of 25:75, tap to RO. I also switched buffers and am now using Acid Buffer, which if I understand correctly, consumes some of the KH, which then also lowers the GH value. Using this mix my aquarium hardness is reduced to ~25 ppm, and 90% or so of the eggs become fertilized.

However, since making this last change to the water chemistry the pair will occasionally fight, sometimes very aggressively, to the point that I must separate them with a divider. Lately though, they have been getting along fairly well, but after each of the last 6 spawns all the eggs, and once the newly swimming fry, are all eaten. I had observed the male eating the eggs after one of the spawns and figured he was the culprit, so last night after they spawned I removed him to another tank. But then sometime today mama devoured all the eggs. Arrrggg!

My fish are housed in a 33 gallon bare bottom aquarium. I run two filters: an Eheim 2213 canister filter with varying sizes of foam and gauze, and PURA NitrateLock, as well as an old Aquaclear with a foam block and Purigen. Water parameters are pH 6.5, temperature 30C (86F), Hardness 25 ppm, ammonia 0, nitrite 0, nitrate < 2 mg/L. I usually perform 50% water changes every day or two.

All the post I’ve found on the internet usually pertain to younger, less experienced pairs, in which the advice offered by others is to let them gain experience with subsequent spawns, and that they will eventually get it right. However, my pair seems to be going in the other direction. What could possibly be the problem?:confused:

mmorris
02-22-2010, 11:48 AM
So, you purchased a confirmed pair of discus, and now the parents are eating the eggs/fry. You had six batches of eggs, and I assume only once did fry actually hatch? I take it they are eating the eggs before you can tell if they are viable? You need a tds meter in order to get the correct mix of ro. You might want to screen off the eggs so you can see if they hatch, but if the female ate the fry/eggs, you might want to try removing the female the next time.

Moon
02-22-2010, 01:48 PM
You are running two power filters in a 33g tank. I think the water movement created by these two filters may be the problem. If there is too much water movement the male may be be able to fertilise the eggs effectively.
I just have one sponge filter in my breeder tanks.
Also as Martha suggested check you TDS vakues.

Rob321
02-22-2010, 03:07 PM
Actually the pair has spawned a total of 11 times, but only the last six or seven spawns have been in water that was soft enough for fertilization, shown by darkening of the eggs.
During the earlier spawns where the eggs would all go bad the pair would fan them continuously for four to five days before eating them, which at least made me believe that they were very devoted to those eggs. On two occasions the eggs hatched. One of those times I had moved the eggs into a 10 gallon tank with methylene blue. After they hatched I put them back with the parents, who ate them not long after. Years ago I had a pair of brown discus that would immediately adopt the wigglers back after I hatched them out separately, so I thought it was worth a try, but I wasn’t surprised when it didn’t work for this pair. The second time the eggs hatched the fry got to the stage where they were attempting to leave the spawning site to attach to the parents, and the pair were busy catching them and spitting them back on the rock. I went out for a few hours expecting to come home to the sight of the parents surrounded by their brood, but when I returned all the fry were gone.

I don’t have a TDS meter as of yet, but I have been using an Aquarium Pharmaceuticals GH & KH test kit, so I believe that my water hardness isn’t an issue for viability, but could it be a factor as to why they eat their eggs? What values do you think are optimum?

Yes, the female ate the eggs this last time, the day after I had removed the male. I will try removing the female the next time.

As far as flow conditions go the currents in my tank are actually very gentle. The Eheim outflow has a spray bar, into which I had drilled a couple more offset rows of holes and have positioned it vertically in a back corner, so the water seeps out over a 90 degree angle. The Aquaclear is an older style of their filter that I’ve had for about twenty years, and I prefer it to their newer design. It has a stopcock that when closed (as I use it) the flow out of it is reduced to not much more than a trickle. However, immediately before each time the pair spawn I unplug the Eheim and remove the intake tube from the Aquaclear. You can’t get much calmer water that that.

mmorris
02-22-2010, 05:46 PM
You are running two power filters in a 33g tank. I think the water movement created by these two filters may be the problem. If there is too much water movement the male may be be able to fertilise the eggs effectively.
.

Good catch. :)

Rob321
02-23-2010, 02:39 AM
Actually the pair has spawned a total of 11 times, but only the last six or seven spawns have been in water that was soft enough for fertilization, shown by darkening of the eggs.
During the earlier spawns where the eggs would all go bad the pair would fan them continuously for four to five days before eating them, which at least made me believe that they were very devoted to those eggs. On two occasions the eggs hatched. One of those times I had moved the eggs into a 10 gallon tank with methylene blue. After they hatched I put them back with the parents, who ate them not long after. Years ago I had a pair of brown discus that would immediately adopt the wigglers back after I hatched them out separately, so I thought it was worth a try, but I wasn’t surprised when it didn’t work for this pair. The second time the eggs hatched the fry got to the stage where they were attempting to leave the spawning site to attach to the parents, and the pair were busy catching them and spitting them back on the rock. I went out for a few hours expecting to come home to the sight of the parents surrounded by their brood, but when I returned all the fry were gone.

I don’t have a TDS meter as of yet, but I have been using an Aquarium Pharmaceuticals GH & KH test kit, so I believe that my water hardness isn’t an issue for viability, but could it be a factor as to why they eat their eggs? What values do you think are optimum? :confused:

Yes, the female ate the eggs this last time, the day after I had removed the male. I will try removing the female the next time.

As far as flow conditions go the currents in my tank are actually very gentle. The Eheim outflow has a spray bar, into which I had drilled a couple more offset rows of holes and have positioned it vertically in a back corner, so the water seeps out over a 90 degree angle. The Aquaclear is an older style of their filter that I’ve had for about twenty years, and I prefer it to their newer design. It has a stopcock that when closed (as I use it) the flow out of it is reduced to not much more than a trickle. However, immediately before each time the pair spawn I unplug the Eheim and remove the intake tube from the Aquaclear. You can’t get much calmer water that that. :)

Moon
02-23-2010, 11:41 PM
I've got a pair of checker boards that spawned quite a few times and ate the fry when they hatched or when they just went free swimming. Just a couple of days ago the same process but the fry attached and both parents are doing fry duty.
This is a young pair about 18 months old. They just needed the experience to get it right.
So the key word is PATIENCE

Rob321
02-24-2010, 06:46 AM
Ah yes, PATIENCE … it’s definitely the most important key, at least on my ring.

It’s just that, well, I seem to frequently misplace my ring of keys.

For instance, just last week I had to literally climb up to my balcony and break in to my apartment…what a pain in the nether region that was. Anyway, enough about my other shortcomings, lets focus on the ones directly related to my fish.

My concern is that my proven pair, that seemed to have the whole process figured out…at least before I got my hands on them, is now not liking something that I am doing (i.e., providing) for them or their environment. They successfully spawned and raised three batches while residing at the LFS, but now won’t follow through.

One line of my thinking that I haven’t mentioned yet is that I believe my pair may have picked up gryodactulus from a trio of Corydora sterbai that were housed together for a few weeks last Nov/Dec. The Corys were removed from the discus tank because they and the discus were both showing signs of fin flicking and scraping. Since then I’ve treated the pair with proper dosages of PraziPro, Life Bearer, Lifeguard, Parasite Clear, and Coppersafe, but the problem still persists. The pair is very healthy and colorful but I do notice both occasionally fluttering their dorsal and anal fins, as well as flicking with their pelvic fins. I haven’t done microscopic exams of scrapings to determine that it really is gryodactylus, however there aren’t any signs of respiratory distress, so I’m hopeful that it is not Dactylogyrus.

Within the next couple days I am planning on setting up two more tanks, one for a bath and another as a temporary home-away-from-home. I’ll drop the pair into a bath of 10 mg/L KMnO4 (potassium permanganate) for 20 minutes or so, and then put them into their temporary home, while I nuke and restore their 33 gallon home.

Do you think a mild case of the flukes could be causing my Good Pair Gone Bad syndrome?

Moon
02-24-2010, 10:36 AM
I think you have given them enough medications to last a lifetime. You won't completely erradiacte flukes. A little flicking is OK. I would not medicate them any more. Just watch them. If they are scratcing against objects you might try a FMG medication like Quickcure. I use just one dose and that's it.
Leave them alone and enjoy them. They will do their thing eventually.