Cories Keep Dying

Crissytal · Post by **Crissytal** » 02 Jul 2003, 05:01

Last week I purchased some new fish, 3 skunk cories, 2 Trilineatus cories, and 10 Neon Tetras. There fish were not added to the aquarium all at once. I started noticing one of the skunk cories was not schooling with the other two. I kept an eye on it. It would just sit by itself for hours and not move. It would be gasping for air. When it swam it would roll or spin. There were no physical signs of sickness like ich or velvet. The water parameters of the aquarium (55-gal) are all in acceptable ranges. I did not know what to do for the poor cory so I put it down (I hate killing anything

). It was clearly suffering. The skunk cory was the first that I lost out of the bunch. A few days later I bought 2 Trilineatus to keep my original one company, along with 5 more neons. They were all fine that day, and the next. Then I started noticing one was hanging back from the group (all my cories, Skunk and Trilineatus school together). It would start gasping at times and would not eat. Again there were no physical signs of fungus, ich, or whatnot. A few days later it died. It never did exhibit the spinning/rolling as the other did. Now my small albino cory is gasphing HEAVILY. I have had it for months. I just noticed this today. Thoughout this time I have lost 4 out of the 10 Neon Tetras. They are not showing any signs of illness either. I just wake up the next day and find one or 2 is missing. All that is in the aquarium is: 1 male betta (very passive), the cories, 1 glass/ghost catfish (I know they need to be in groups, I'm working on that), 1 otto (working on that too), 2 small S. Nigriventris, and the remaining neons. What is going on? Can someone please help me? I've tried to do some research on this, but I just have no idea where to begin. I REALLY hope I will not lose my remaining fish...I have become very attached to them

. I apologize for such a long post. Thanks everyone.
Crystal

Allan · Post by **Allan** » 04 Jul 2003, 01:32

Hi Crystal

Long posts are nice, some are to brief imo.

I think the first skunk cory that died suffered from internal damage from the transport. Reads like it to me.

The gasping for air is quite normal, but if they are really doing it much more than usual, i would change some extra water to bring nitrates and organic waste down, and ad a powerfull air pump to the aquarium.

But right, something is wrong in the aquarium, but i can't read what it is. What do you mean, when you say that the water parameters are all in acceptable ranges? - What are your water parameters?

I find one thing out of place: The Betta. I woulds find it hard to keep these guys with most cories, as the cories like fast current, det bettas don't. What is your filters turnover rate in this tank?

Kr
Allan

Crissytal · Post by **Crissytal** » 04 Jul 2003, 04:48

Hello Allan.
I just tested the water parameters again to be sure. The readings are:
Ammonia: 0
NitrIte: 0
NitrAte: 20 (a little high I know)
Total Hardness: 120
Total Alkalinity: 120
pH: 8.4

The hardness/alkalinity/and pH have remained the same since the day I filled the tank. The betta stays mostly on the opposite side of the tank, away from the filter. It doesn't seem to bother him. I currently only have one filter. It is a Whisper Power Filter 60. It is suppose to be good for 30-60 gallon aquariums and the gph is 330. I have it turned to max filtration. I have also added a 14" bubble wand which my cories absolutely love.

I have lost all but one Neon Tetra. I'm not sure exactly why. They didn't appear to have the Neon Tetra Disease. I know they like softer water, but they were purchased from a local fish store which has about the same water parameters as I do...so the guy claimed.

The small Albino cory that I mentioned is doing better. He is swimming around, seems to be energetic, and is eating. I have noticed some shimmering/flashing against the sand/decorations, but not a lot. There aren't any physical signs that I can see of skin irritation. Maybe it's because of the nitrAtes being a little high? Anyway I hope he continues to recover to full health. I'll probably be doing another water change within the next few days. Thanks.
Crystal

Nina · Post by **Nina** » 04 Jul 2003, 10:44

I think that the pH might be a bit too high. Where did you buy the fish from and did you ask how long they had been in the shop before you bought them? If the fishes had just arrived to the shop say a week ago they would not have had enough time to adjust to their new environment before they were again transfered to a new environment (your tank). This is a very important aspect that one doesn't often think of. Especially if your fish(es) were imported from the wild they have had quite a long journey and need the rest, at least 2-4 weeks. Stressed-out and tired fish have little chances of survival and even the slightest extra stress such as a little higher pH or nitrate concentration can be too much. In my opinion, it's always best to make a bigger water change before introducing new fish. Preferably you should have a quarantene tank where you keep new fish for 2-4 months. And never buy recently transported fish. It may even be that they have been starved for so long during transport that their digestive track is irreversibly damaged.

Allan · Post by **Allan** » 04 Jul 2003, 13:09

Yep, that pH and alkalinity/hardness is way to high for your fish imo.

I would try and bring the pH down to at least 7,5, or prefarably even lower. I think this would stop your Neon's from dying, and the Cories would love it as well.

Your tanks turnover rate seems to be fine, as long as you are not trying to breed them

If you can't get a hold of some soft water, you can maybe try some spaghnum filtering (I think peat is the correct english word).

Kr
Allan

Nina · Post by **Nina** » 04 Jul 2003, 13:48

Since the water is so hard, you may experience some difficulties in lowering the pH though. The harder the water, the more it's buffered against changes in pH
So the idea of trying to obtain soft water is good and should help you to lower the pH too.. .

I have myself tried peat filtering but it had no effect on my water. My tapwater is of pH 7,6 which is a little high but still okay for corys - my pandas spawn in it but the more demanding corys don't.

Carbon dioxide fertilization is one good method for lowering the pH (the only one that has worked for my water) and helps enhance plant growth too. Healthy well growing plants help in turn to keep the water quality good.

Crissytal · Post by **Crissytal** » 06 Jul 2003, 15:41

Thanks everyone.
I'm not sure how long the fish had been in the shop. There probably was a mixture of old ones with new ones. I think I'm better off leaving the pH and hardness alone. I started a discussion about that in the Tank Talk section awhile back, when my tank was still cycling (Tank Cycling Fishless). The higher pH isn't as bad as pH fluctuation. I would have a hard time keeping everything consistent. Especially for a tank that large. If I ever do want to spawn my cories I'll set up my old 10 gallon and cycle it, and then slowly reduce the pH/hardness using a softening pillow or bottled water. It would be much less expensive on a smaller tank like that, then with the 55-gal. What is Carbon dioxide filtering? I've never heard of that, unless you are talking about the CO2 injection for plants?

All my fish seem fine. I did lose a cory to an eye infection though

. I think my crab is to blame for that. I saw a few tiny red scratches on the cories head, but who knows. But anyway as of right now, all seems well. Thanks everyone for you help.

Nina · Post by **Nina** » 07 Jul 2003, 09:47

Yes, I was talking about CO2 injection, ie. fertilising the plants with CO2 (carbon dioxide). The advantage of CO2 injection is that it doesn't lower the pH too abruptly. The CO2 forms carbonic in the water, which dissosiates into H+ ions (+ other ions). H+ ion concentration determines pH: the higher the concentration the lower the pH (the more acid). That's the basic idea at least, I'm not a chemist but that's how I remember been taught...It worked in my tank, lowering the pH from 7,6 to 7,2.

If you have a heavily planted tank, the plants may use up all the free carbon dioxide from the water which means that there is less H+ ion formation in the water, ie. pH rises. This happens during daytime, when the lights are on and the plants photosynthesize. You could check if the pH is the same in the morning and in the evening. If you notice a rise in pH during the day, your tank would definitely benefit from CO2 injections. Another reason why the pH can rise is if you are using a very efficient pump which circulates the surface water so much that all free CO2 evaporates from the water. During night-time the plants respirate (use oxygen) just as the fish do, so it's recommended that you do not add CO2 in the evening/ during nighttime but instead use air pump to provide enough oxygen for the plants and the fish.