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Harlequin Rasbora problem

22K views 23 replies 6 participants last post by  Norbert93 
#1 ·
Hello everyone,

Over the last three days I've lost 3 Harlequin Rasbora (out of the six I had). The 3 that died seemed to be males. I had 4 males and 2 females. I thought at first that I had been over-feeding them, as two of them got really fat. Then I realized that those two must have been the females when I saw one of them trying to spawn (kept flipping over underneath one of my anubias leaves). My question is, when females are displaying this behavior, is it possible that the males would fight over them?

A couple of days ago, I noticed one of my Rasboras was completely missing his tail fin. This Rasbora died the next day (found him stuck to my filter). One the same day, I found one of my Rasboras dead and tangled in some Java Moss. The day after, I found another dead male floating around. I have 0 ammonia, 0 nitrites, and 20 nitrates. My pH is around 6.8. Temperature is 78f.

The tankmates I have are MTS, 3 Zebra Nerites, 4 Amano Shrimp, and a Bristlenose Pleco.

Did my males have a Battle Royale over the egg laden females? Or is something else happening? They all seem to be swimming around and schooling happily, and they all still scramble to the top during feeding time.
 
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#2 ·
Is it possible that you have something else going on in your water? What type of water conditioner are you using?

Now that your fish numbers are down, you might want to get more females. You could try 3 females for every male and see if the aggression stops.
 
#3 · (Edited)
I'm using Seachem Prime.

Now, one of the females is hanging out in the back near the filter, kind of at a 30 degree angle looking up. The other two are swimming and eating fine. The female in the back came out once or twice when the school (if you can even still call it that) swam by, but then went back into the corner. It came out and grabbed a piece of food, then seemed to spit it back out. I'm going to test the waters again and post my results, then probably do a water change.

Edit: Now the two females are hanging out near one of my anubias', basically not moving. The male is swimming around.

Edit 2: And now they're all moving around again...I don't know what's going on. o.o
 
#4 ·
I tested the water again, all the same as above. I did a 25% water change. I then noticed something I had not seen before, a little white worm swimming around! Looking it up, it seemed to be a nematode. I couldn't snap a picture of it before it went back into hiding, but it was thin and white, and swam around like a snake. Could this be a contributing factor? How can I get rid of them?
 
#6 ·
I have never had aggressive issues with any rasbora, and I have maintained and had spawnings with all three common species in Trigonostigma. I think we need to look elsewhere for the cause.

I've no idea what the worm might be. Some are safe, some not. If it is nematodes, the only external sign on the fish would be the worm hanging from the anus. Have you observed this?

Are there live plants? The nitrate is on the high end of safe, but would be better lower. This in itself is not the issue, just something I spotted.

How long have you had the fish? I'm thinking there might be some internal protozoan or pathogen causing this.

BTW, rasbora are not characins, they are cyprinids, so I've moved this thread to that section.

Byron.
 
#7 ·
Nothing coming out of their anus.

I have a bunch of plants in there.
Bunch of Valls (started with five, but their popping up everywhere!)
5 Java Ferns (Each having like 5-10 new ones coming off)
2 Anubias Nana
Bunch of clumps of java moss scattered throughout.

The nitrates of my water source are actually higher than my aquarium water. They test at ~20-40, so, I can only hope that the plants take in enough of the nitrates. I'm thinking about adding a floating plant, like frogbit, to help some more.

They seem to be a lot more active today. No odd behavior yet from the male or one of the females. The female that was acting odd yesterday is only swimming around in the valls, though. :/

I was thinking about it, and it dawned on me that it could have been a pH swing. I took a tufa rock out, and put a piece of Malaysian driftwood in for my Bristlenose. I'll check the pH again once I get out of bed.

Also, I think two of my snails died...I think. I was lead to believe that the smell would knock me out cold, but they just kind of smelled like snail. One smelled a little worse. Both of their trapdoors are slammed shut. Neither of them have moved at all in the past couple of days..so maybe they are dead, but have not decomposed enough yet. The third one is crawling around but is kind of lethargic.
 
#9 ·
Diagnosing fish disease/problems is very difficult many times, except for an experienced and trained biologist. These fish may have had some issues from long ago. They seem to be improving, so that is good. You might want to increase the frequency of the water changes for a week or two, i.e., instead of once a week do two or three during that week. Believe me, nothing helps fish more than a partial water change. If you read the "advice" sections of TFK or PFK regularly, almost every recommendation includes a water change as the first "treatment."

Check the pH, this is a possible if it was a sudden and significant change. Regardless of that, lowering the pH will benefit rasbora no matter what; this is naturally a very soft and acidic water fish. And they will always be healthier in such water.

Byron.
 
#10 · (Edited)
My rasboras seem to be acting completely normal again. I am still having a little bit of a nitrate problem, though. My tap water naturally seems to have 20-40ppm nitrate, so water changes keep it around 20-40 (which is not good..). I'm going to get some floating plants this weekend to hopefully eat up some more nitrates. In the meantime, I'm doing a small water change ~(10%) every day to keep the nitrates from raising higher than my tap.

My pH has been dipping a little bit every day, but not much. It was at 7.4 before I took the tufa rock out, and now it is equalizing more towards my tap water's 6. I fear that the more frequent water changes I'm doing will make it dip too quickly, but I'll hope for the best. I am trying to get it back to my tap's pH, I learned my lesson trying to mess with my tank's pH. :/

I thought I lost two of my shrimp, but found out today that they actually shed their exoskeleton. They all went crazy when I did the water change (they like to catch all the floating food, I think), and I counted four! I feel bad for taking their exoskeletons away and stealing their extra calcium now, though. :(

One of my snails was definitely DEFINITELY dead. It smelled like foul foul death. Could this have caused some of the fish death? I think one of my other Nerite snails is dead. It hasn't moved in a while, and was one of the two I found upside down one day (the other one being the dead one). It doesn't smell, though.

I'm going to get more plants and hope they will start to devour my nitrates, then I'll get some more Rasboras to make them a happy school again. I'll keep you posted on whether they are improving or not. Thanks again for your help!

As an unrelated note, you are actually one of the reasons I joined this site Byron, :lol:. When I was researching what to do to start my fish tank, this site kept coming up in google searches. Every question I seemed to google was answered by you. You seem to be the most active member on any aquarium forum. :lol:
 
#11 ·
My rasboras seem to be acting completely normal again. I am still having a little bit of a nitrate problem, though. My tap water naturally seems to have 20-40ppm nitrate, so water changes keep it around 20-40 (which is not good..). I'm going to get some floating plants this weekend to hopefully eat up some more nitrates. In the meantime, I'm doing a small water change ~(10%) every day to keep the nitrates from raising higher than my tap.

My pH has been dipping a little bit every day, but not much. It was at 7.4 before I took the tufa rock out, and now it is equalizing more towards my tap water's 6. I fear that the more frequent water changes I'm doing will make it dip too quickly, but I'll hope for the best. I am trying to get it back to my tap's pH, I learned my lesson trying to mess with my tank's pH. :/

I thought I lost two of my shrimp, but found out today that they actually shed their exoskeleton. They all went crazy when I did the water change (they like to catch all the floating food, I think), and I counted four! I feel bad for taking their exoskeletons away and stealing their extra calcium now, though. :(

One of my snails was definitely DEFINITELY dead. It smelled like foul foul death. Could this have caused some of the fish death? I think one of my other Nerite snails is dead. It hasn't moved in a while, and was one of the two I found upside down one day (the other one being the dead one). It doesn't smell, though.

I'm going to get more plants and hope they will start to devour my nitrates, then I'll get some more Rasboras to make them a happy school again. I'll keep you posted on whether they are improving or not. Thanks again for your help!

As an unrelated note, you are actually one of the reasons I joined this site Byron, :lol:. When I was researching what to do to start my fish tank, this site kept coming up in google searches. Every question I seemed to google was answered by you. You seem to be the most active member on any aquarium forum. :lol:
Thank you indeed for your kind words; I do sincerely appreciate them.

On the dead snail, this is not likely to cause any issue if we are talking the common small snails; one of those large Mystery type might, that is a more significant impact.

Let the pH lower, there will be no problems there.

The nitrates may require more intervention. Smaller-volume water changes is a first step, once the tank is lower to begin with, as this will prevent sudden significant increases. If this plus the plants don't handle things, there are some good methods we can discuss. Other members like AbbeysDad have this issue and have successfully dealt with it.

Byron.
 
#12 ·
First update!

My pH has lowered to 6.4.
Ammonia and Nitrite still at 0.
Nitrate hasn't changed from my tap at all. (~30) This is a good and a bad thing. It's good because my plants seem to keep it from raising. Bad because they aren't lowering it and it's still too high. :/

All of my Nerites are now dead. I think the damage was already done with those guys. :/

All three of my Rasboras are active and acting normal.

My catfish is still alive, but I have not had him long enough to know if he's acting normal. he mostly just comes out at night and runs away when he sees me haha.

As far as I know all of my Amano shrimp are still alive. I have not found any dead shrimp, and they are experts at hiding.

Who knows if my MTS are still alive. I didn't see any last night. I still only had about 10 though, so there is a good chance I just couldn't find them.

I wasn't able to add any plants. I went to work Friday and was stranded because of that storm until yesterday night around 6. I dosed my plants using this method Non CO2 methods - Page 2 - Aquarium Plants and Excel to try and boost their growth on Thursday. With the exception of the Potassium Nitrate (which I skipped for obvious reasons), I dosed about half of what that said to see what happened with my water and plants. I dosed .1ml per gallon of Excel. When I came home Sunday night my Java Ferns had EXPLODED, so I hope they will start eating some more Nitrates It's also possible that my nitrates were higher than my tap water (>30), and the Java Ferns have been using them up. They may have lowered them back to the level of my tap water, and I just happened to catch them here. I wasn't home to check the water every day thanks to Nemo, but I'll test it again in a couple of days to see if it's gone down at all. Also, I'll do the full dosage posted in that thread on Thursday again. Weather permitting, THIS weekend I'll go get some more plants. My gH test kit is coming in the mail right now, so I'll post my gH when that comes in.
 
#13 ·
Nitrate hasn't changed from my tap at all. (~30) This is a good and a bad thing. It's good because my plants seem to keep it from raising. Bad because they aren't lowering it and it's still too high. :/

I wasn't able to add any plants. I went to work Friday and was stranded because of that storm until yesterday night around 6. I dosed my plants using this method Non CO2 methods - Page 2 - Aquarium Plants and Excel to try and boost their growth on Thursday. With the exception of the Potassium Nitrate (which I skipped for obvious reasons), I dosed about half of what that said to see what happened with my water and plants. I dosed .1ml per gallon of Excel. When I came home Sunday night my Java Ferns had EXPLODED, so I hope they will start eating some more Nitrates It's also possible that my nitrates were higher than my tap water (>30), and the Java Ferns have been using them up. They may have lowered them back to the level of my tap water, and I just happened to catch them here. I wasn't home to check the water every day thanks to Nemo, but I'll test it again in a couple of days to see if it's gone down at all. Also, I'll do the full dosage posted in that thread on Thursday again. Weather permitting, THIS weekend I'll go get some more plants. My gH test kit is coming in the mail right now, so I'll post my gH when that comes in.
Dealing just with the nitrate issue. Don't expect the plants to have much of an impact. Most will use ammonium first, and only when that is insufficient will they turn to nitrate. But 30ppm nitrate in the source water is not good to begin with, and this is not going to lower significantly anyway.

Nitrates should not be allowed to rise above 20ppm, and keeping them at 10ppm or lower is better for the fish. You are going to have to deal with the nitrate in the tap water. AbbeysDad has posted on how to achieve this, as he has the exact same issue.

Byron.
 
#14 ·
I added a Giant Hygro and two clumps of Wisteria floating to my tank. I think I found the post you were referring to and am researching De*Nitrate, Matrix, and Purigen. I'll let you know if the new plants make any difference, and if not, if the Seachem products do.
My Rasboras seem to love the new floating Wisteria though! I think a piece broke off and one of them actually ate it. Although probably only because it fit in her mouth haha.
 
#15 ·
Finally got my test in. My tank water and tap water have the same levels. The gH is 4 (71.6), and the kH is 1 (17.9).

At least I'm assuming the kH is 1...the test (I'm using API's liquid test) says to add drops until the liquid turns from blue to yellow. After the first drop it's yellowish..there never is any blue. I added more drops and it just made it darker yellow.

So...what's a good kH? I feel like 1 is NOT a good level.
 
#16 ·
Finally got my test in. My tank water and tap water have the same levels. The gH is 4 (71.6), and the kH is 1 (17.9).

At least I'm assuming the kH is 1...the test (I'm using API's liquid test) says to add drops until the liquid turns from blue to yellow. After the first drop it's yellowish..there never is any blue. I added more drops and it just made it darker yellow.

So...what's a good kH? I feel like 1 is NOT a good level.
I never fuss over the KH. KH has no effect on fish. It does act as a buffer for pH, but if you have soft water fish they prefer it acidic so I don't worry about this. I let my tanks do what they want with respect to the pH, and with regular water changes they remain stable.

Byron.
 
#18 ·
My Purigen came in the mail. It didn't really fit in my stock Aqueon filter (I bought one of those deluxe kits), so I bought a bigger Aquaclear 50. I'm not using the carbon insert (replaced it with the Purigen.) I'd like to eventually not use the Purigen at all (maybe use it in buckets overnight or something) once my Nitrates in my tank go down considerably. Matrix has not come in yet.

Almost everything in my tank is dead. >< I put 4 more Rasboras in there because I felt my 3 were getting lonely. The last of the original 3 Rasboras I had went, but the other 6 are doing fine. My Amano Shrimp all went. One at first, then all but one went about 4 days later. The last one lasted for another week. I put 4 more Nerite snails in the tank. They died overnight. >< Even all of my MTS have died (I thought these things were supposed to be impossible to get rid of!) The one that hurt the most, my little baby BN Pleco passed away. :(

Not sure if my filter's current is too strong. It is rated at 200 gph, but it is adjustable. The Rasboras seem to LOVE it. Three of them played in the current for a good long while.

I also picked up some R/O water from Petco and mixed it in with the water change. Not economical at all ($4 a gallon ><), but hopefully it helps for now. I'm also going to test my water at work tomorrow. If it's not too far off in terms of hardness, I may just fill up some 5 gallon buckets and bring them home. I may get some weird looks, but I'm just stealing water, so that's okay, right? :lol:

My Giant Hygro is doing Okay. A few leaves have fallen off, but there seem to be 5 or 6 new ones growing. A bit of my Wisteria died. Some new Wisteria has grown at the same time. So, I think maybe it was the shock of a new tank maybe. Either way, they seem to be growing fine now.
 
#19 ·
I read through this thread to refresh my memory. I have a couple observations.

The shrimp probably won't manage in such soft water, so forget them. Ths is not the time to start fiddling with water parameters. And for the fish, what you have is ideal. So be satisfied with that.

Same may be true for the snails. But Malaysian Livebearing will thrive in any water, even in my very soft zero-GH water they are in the hundreds. There may be some in the substrate.

The death of the original fish, but not of subsequent acquisitions, is actually encouraging. We don't know what may have affected the original fish.

Byron.
 
#20 ·
Another update!

All of my remaining Rasboras seem to be doing great! The nitrates in my tank are still a little high (looks like between the 30-40 range). But, I got some Matrix and Purigen. I'm now using the Matrix in my tank. I also got some extra Purigen and Matrix. I set these up with my old HOB filter and a 5 gallon bucket. I let it run overnight and tested the water in the morning...0 nitrates! Hooray for clean water for water changes! So, hopefully my tank nitrates will go down considerably (since I'm no longer putting new ones in!)

It seems the nitrate level in my tap has gone down by itself as well. (10-20 nitrates). Probably due to it being Winter..I'll check it again in a few months. Anyways, thanks for all your help! I can't wait to restock my tank and put some pictures up!
 
#21 ·
I like good news.:-D
 
#22 ·
Hope everything is still going well in your tank, an interesting thread, i will second the thanks to Byron, always there for help.

I have Harlequins and Amano's together, one of the harlequins just died no sign of any damage and looked in great condition. Also when i do water changes my shrimp go mad and chase all over the place, it is a good time to make sure they are all well.
 
#24 · (Edited)
Please Help!

Hy everyone!

Something very similar is going on in my 52 l tank right now and I don't know what to do anymore.
First of all I am a beginner, I set up my tank in august this year, it is a 52 l tank, with a few plants (1 moss ball, a few Anacharis Elodea and Cryptocoryne Willisii or Becketti, I am not sure which), a piece of wood, a plastic decoration, filter and a heater.
The water temperature is 24,5-25 celsius, and the water parameters are:
NO3= 15 ppm
NO2= 0ppm
NH4= <0.05 ppm
pH=7.2
GH= >7( >125 ppm)
KH= 6 ( 107 ppm)
Cl2= 0 ppm

And here is what is happening: So I set up my tank in august this year, and I let it cycle for 2 weeks, using fish food as ammonia source, and I monitored the water parameters, and also did a water change once a week. After the first two weeks the cycle was over, so I added my first two fish a black molly an a Sterbai's cory. I was careful not rise too fast the bioload, so I builded up my stocking slowly, while always monitoring the water parameters. At the end of september I've added my last fishes, ending up with: 5 Corys (2 Albino, 1 Sterbai's and 1 Panda) , 1 female Black Molly, 1 young, male Albino Ancistrus, and 6 Rasbora Espei.

At the beginning I measured the water parameters daily and I did 2-3 (30%) water changes/week, because I was scared of an ammonia or nitrite spike, cause I've added the 6 Rasboras last, and I feared that would rise the bioload too much, but I had no problems. After a week or two, I went for a week without water change, but I kept measuring the parameters daily, and did a 35-40% water change on the seventh day, on the next week I did the same thing, and since there were no ammonia or nitrite spikes, and the nitrates did not reach a dangerous level, I went on with only one 35-40% water change/week, and I also measured the parameters once a week before the water change, but sometimes I also checked it during the week and it was all right every time. No pH fluctuations, no ammonia or nitrite spikes.
When I do a water change I also vacuum the gravel, and I clean the sponges from the filter in the tank water that I just took out. I use tap water to which I add a water conditioner named Clorocid, and I let it stay for minimum 24h.
I feed my fish once a day, making sure not to overfeed them, and variate their food daily, between: granules, flakes, dried daphnia, and sometimes I give a boiled pea to my Ancistrus, of which the Black Molly also likes to eat.
The problems started with my Black Molly somewhere at the end of october, on his body, on one of his side, near his tail fin appeared a white spot, it was small, and it wasn't fuzzy looking, so I believe it wasn't fungus, since it was only one spot, I am sure it wasn't white spot disease too. I started too look it up on the internet and I found out that Black Mollys like brackish water and I thought that is her problem, but since I had corys too which, I understand, are sensible to salt I could not add too much salt to the water. I gradually raised up the salt concentration to 0.1 %, with the water changes. After a few days the white spot just disappeared. But if I stopped adding salt it came back on another spot. One they I saw that she had 2 white spots already, one near her tail fin, and the other on her had behind her eye.
I added salt again and the white spot from her side disappeared but the one on her had did not. A couple of days later another spot (bump) appeared on her side, but this one started to grow too. I raised the salt concentration to 0.2% gradually, and it started to disappear but It left a hole on her side, which healed up over time. This time the white spot on her head was still there.
During this time all of my other fish were good, very active, colorful (except the albinos :grin2: :grin2: ), until one day I found my cory panda dead when I got home from work. It was active as usually the day before, and didn't show sings of illness at that morning neither.
A week later my Sterbai's cory started to look sick, he got a bit skinnier I think, than lost his color, and before he died he swam weird, and had a bit of a curved body.
I checked the parameters, and they were OK, but still, after their deaths I did a water change 2x /week.
After the second cory died more then a week later I saw that my two albino corys and my black molly started to have fin rot. At this point I set up a hospital tank and started treating them with Ektol bac Plus 250 from JBL. The two corys got better, and first the molly too, but later her body just curved a bit, since the treatment was over I put back the two corys to the main tank, and left molly in the hospital tank.
Before adding back the two corys, one of my Rasboras jumped out of the tank, I found him dead on the floor when I got home. I thought that he got scared of something, and I read on a forum that they are jumpy. But unfortunately 3-4 days later I saw that one of my remaining Rasboras started to have fin rot too. The next day all of them had clamped fins. At this point I've decided to treat my main tank, but I did not want to kill my beneficial bacteria, so I searched for a treatment that does not kill them, so I ended up adding Sera omnipur to the tank. Before starting the treatment I decided to but back in the black molly too and I also bought 2 more Rasbora's to have a school of 7. I decided to do this cause I thought that if I already have to treat the whole tank I should add the new fish and get rid of an eventual disease they could carry, and also to try another treatment with the black molly.
I've added the treatment 2 days ago and it has been a disaster since then :crying::crying::crying::crying:, because one of the new Rasboras jumped out of the tank, my molly now has clamped fins, her body is curved, and still has fin rot. A couple of hours after I added the treatment the Rasbora that started to develop fin rot at his dorsal fin just turned upside down and swam like that around the tank and he could not get back in the right position, so I decided to do a salt dip to see if he recovers, I kept him there fol 30 min, and It seemed like it is helping him since he got back in the right position, but he was still weak. After I put him back in the tank he died in a couple of minutes.
Right now 3 of my Rasboras have their tail fin missing, and this happend today, in the morning they till had them and I kept checking on them and saw that it starts to disappear, like it's dissolved in the water. It is very weird :O :O :O :((. One of them tarted an hour ago to swim weird started to lose balance , so as soon as I finish posting this I will go ahead and euthanize him.
I forgot to mention that when I started the treatment I also added an airstone to have better aeration.

Do you guys have any idea what is happening, and why things got worst when I started the treatment? The parameters I gave you are current I just checked them before starting to write this post. I am sorry for this long post, but I wanted to give you all the information I have so that you can help me.
 
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