Dwarf Neon Rainbowfish acting strangely.

[Kris_H]

Hello all, my first post here.

Recently I purchased 5x Dwarf Neon Rainbows to go into my 200l tank. The tank is about 2 years established, cycled and has been monitored daily since I bought the new fish a week ago.

The new fish have been acting abnormally ever since I got them and seem to be worse for wear today. When I first put them in the tank I did my usual acclimation procedure which is to float the fish bag in the tank and then over the course of an hour or so change bag water for aquarium water.

From what I've read, Neon Rainbowfish should be active in the tank and keen eaters. The ones I have, had taken up residence near one of the pieces of driftwood in the tank and could sometimes been seen eating off of the driftwood. They'd never attempt to actively get food that I'd put into the tank. On occasion they would take a piece of flake however it would be spat out after a attempt at a chew. The other thing they would do is stay at the surface similar to what a guppy might do when they're after floating foods; except unlike a guppy the Rainbowfish would actively avoid any floating foods.

My first though was there must be Nitrite in the water; checked with the API liquid kit and nothing, also checked with a different liquid test kit (brand new NT Labs - Aquarium Lab) and again nothing. Also checked ammonia with both test kits and not a trace of either. I've been running the air stones on permanently ever since I noticed this behaviour worried that maybe they were oxygen deprived but it has made no difference. None of the tank mates had shown signs of any distress either.

Today I noticed things have gone downhill, one of the Rainbows is swimming into objects almost as though he has completely lost his vision (cannot see any cloudiness of the eyes) and the others are all glued to the surface of the water and still wont accept any foods . None of them are showing any external symptoms of anything being wrong, there are no clamped fins, no spots, no lumps and their gills look fine. The only thing that does look off is they're not completely coloured up, but then they're still juveniles so I wouldn't expect them to be.

Now for tank stats:
Size 120cm x 45cm x 40cm : 200L
pH: 8.1
dh: 14
Temperature: 26c
Ammonia: 0ppm
Nitrite: 0ppm
Nitrate: 5-10ppm

Tank is well planted with both normal and floating plants. Plenty of areas for fish to hide in with rocks stacked to form a cave system and large driftwood pieces. Whole system is filtered with an established external filter running normal media plus Seachem Purigen. Water changes are carried out 3 times per week totalling a water change of 35%.

Tank mates are as follows:
6x Cardinal Tetra
5x Glowlight Tetra
6x Albino Cory
6x Guppy
All of those fish have been in the tank for two years now and I've not lost any or noticed any signs of distress. I know that the tank water is too hard for the Tetras and Corys, I bought them back when I wasn't fully researched on fish and their water requirements. I purchased the Dwarf Neon Rainbowfish because I had read they'd thrive in harder waters.

I've been lucky and have never had an outbreak of disease in any of my tanks so I'm at a bit of a loss as to what I can do here. I did treat the entire tank with praziquantel that I had once purchased and never used however it had no effect on the Rainbowfish. The other fish didn't seem to react at all to the praziquantel so I'm hoping I didn't stress them overly for nothing. Is it worth trying to treat the poor Rainbowfish with anything or would it only cause them stress for nothing?

Thanks.

 

[neoyyf]

I just realised that you did state ph

It is a ph problem. They are comfortable in ph 6-7. However i dont know how to help this situation. Try googling. Or maybe another member can help

 

[neoyyf]

It might help ti ring up your LFS and ask about their water parameters. Perhaps they lowered the ph in that tank, ask them how they are doing it. I suspect with a lot of driftwood or blackwater. But be careful because you may affect the other fish if you start messing around with ph

 

[Kris_H]

I've asked them before if they did anything to their water. Apparently it's straight conditioned tap water all filtered on a shared sump. They don't run any of it through a RO unit or anything similar. I was under the impression that pH wasn't an issue as long as it was stable, but then again to have all of these fish acting as they are makes me think it could be the culprit. I had heard that these Rainbows would do well in hard water but that clearly isn't the case.

The fish that was swimming erratically unfortunately passed on so just left with the four now. Gutted. Having hard water and wanting to keep fish isn't particularly fun.

 

[Essjay]

Most rainbowfish need hard water but dwarf rainbows are an exception. Your hardness at 14 dH is right at the top of their range - which is 5 to 15 dH. The Celebese rainbow would fit your tank and likes hard water. The Madagascan rainbow is a bit larger, and 120 cm long tank is the minimum for these fish so you might be OK with them.

 

[Byron]

I'm not disagreeing this may be a water parameter issue. But there are a couple of ways to try and pin it down. First, how long has the store had this group of fish before you bought them? If the store water is as you say (and most stores do this, I'll come back to that) and close to yours, I would not expect this reaction just from the parameters unless the fish are doing the same in the store tank.

It is seldom useful to assume fish will be fine in your water just because the store where you acquire them has similar water. Parameter differences can take some time before they manifest themselves in fish problems and death. The GH for example works internally, and soft water fish will have shorter than normal lifespans due to the buildup of calcium in the kidneys, but this is not going to happen in a few days, or even months depending upon the specifics. A study in Germany back in the 1980's showed that cardinal tetras lived shorter lifespans in relation to thee GH; the higher the GH, thee shorter they lived. But it was still months and a few years. That does not mean the fish are "OK" just because they live a few months...quite the reverse. And the other thing here is that stores hope fish will not be in their tanks very long; the sooner they sell them, the better, as maintenance costs money. Nothing wrong with that thinking, but we must realize that the store is not providing "ideal" conditions but only temporary, and some fish can manage temporary but not permanent.

A pH shock might have caused this; do you know the pH of the store water compared to your tank water? Acclimating fish by mixing tank water with the bag water, whether it is done using say half a cup at a time, or more slowly by the drip method, is not very likely to make much if any difference. I was discussing this only last week with Dr. Neale Monks, and he pointed out that "acclimation" like this takes weeks, if it is even possible. After all, fish that have evolved physiologically over thousands of years to function best in a very specific set of parameters are not going to be adjusting very well if the intended parameters are significantly different.

Back to the issue here...the fish themselves might have been diseased or somehow injured (again the state of those left in the store might clue you in). They might have been injured during netting (this can cause serious internal injuries) or transport, and the incredible stress associated with both doesn't help. Or there could be something else in the water that the existing fish are dealing with, but the newly acquired fish found too significant.

Byron.

 

[Kris_H]

I'm not sure what the pH of the store water is but I'll ask tomorrow. I'd hazard a guess it is the same as the water here because they are only a 5 minute walk away and I'm certain they're served by the same water main. Whenever I've purchased fish from them in the past I've never had acclimation issues like this. Also for what it's worth a good friend of mine hasn't really seen the same issues in any of his fish that he has gotten from there. I know when they get new fish in they wont sell them for a while because they adjust them to the water first. I really cannot remember how the fish were behaving at the store when I bought them until I go back there and take a look.

I completely understand that soft water fish cannot truly thrive in hard water, the cardinals, glowlights and corys were bought years back when I first started keeping fish. I knew about cycling but was ignorant to the difference between soft and hard water fish then. I had honestly thought that Dwarf Neon Rainbows would do well in the water I have but apparently not. The tetras and corys do at least appear to be content in their less than ideal water, they're lively, colourful and always up for food. I've always run chemical filtration in my tanks so no idea if there is any pollutant in the water that you say the existing fish could have gotten used to.

I'm not really sure what to do with the poor Rainbows. The shop wont take them back as I've had them for a week now. The options I have are: just let them be in the tank in the hope they get better; probably the least stressful for them. Try to medicate them; which from what I have read achieves half of nothing the majority of the time or give them away, likely to be placed in the same crummy water.

@essjay Cheers for the Rainbowfish suggestions. The Celebese rainbow is quite the looker but annoyingly it's not listed on the stock list for my fish shop. To be honest I'm starting to feel a bit bummed out about fishkeeping as a whole. As awful as it sounds I'm considering seeing my current fish through and then selling the tanks. Water here is just unworkable for anything I really want to keep and can get hold of. Guppies are lovely but just having loads of males means they're constantly harassing each other. I love the schooling fish and really love the cory cats but I just don't think it was meant to be sadly.

 

[Byron]

Some of my last post may have been misunderstood. I am saying that in spite of possible parameter differences, it is not clear to me that this and only this is the problem with the rainbowfish. The demise was just too sudden. That is what I was getting at. The continuing life of the other soft water fish, and much more sensitive soft water fish in terms of their preferred parameters, is in stark contrast to the rainbows reacting within days.

A pH or temperature shock could bring this on. So also could something else in the water. Or just not very healthy rainbows to begin with. Or the injury.

I certainly do not recommend any "treatment" in the way of some medication, unless one is reasonably certain of the issue and the treatment is the best way to handle it. Stress to all fish, sick and healthy, from all medications, chemicals, etc should not be discounted because it is fact. Even healthy fish are stressed by any medication entering their system. My reaction at the first sign of something not right with fish is a major water change. Frequently this alone has solved whatever it was; but it certainly won't cause more harm, assuming the parameters between tap and tank are relatively the same.

 

[neoyyf]

You can have low ph and hardwater which is what these fish need. But usually hard water from cities is high ph. Im in the midlands so my water is hard and high ph like yours. I found this really detailed site listing all the fish and plants we can keep

http://www.wetwebmedia.com/fwsubwebindex/fwhardness.htm

I would add that you can also keep most invertebrates (shrimps, snails and crabs). And java moss and moss balls

 

[Kris_H]

Some of my last post may have been misunderstood. I am saying that in spite of possible parameter differences, it is not clear to me that this and only this is the problem with the rainbowfish. The demise was just too sudden. That is what I was getting at. The continuing life of the other soft water fish, and much more sensitive soft water fish in terms of their preferred parameters, is in stark contrast to the rainbows reacting within days.

A pH or temperature shock could bring this on. So also could something else in the water. Or just not very healthy rainbows to begin with. Or the injury.

I certainly do not recommend any "treatment" in the way of some medication, unless one is reasonably certain of the issue and the treatment is the best way to handle it. Stress to all fish, sick and healthy, from all medications, chemicals, etc should not be discounted because it is fact. Even healthy fish are stressed by any medication entering their system. My reaction at the first sign of something not right with fish is a major water change. Frequently this alone has solved whatever it was; but it certainly won't cause more harm, assuming the parameters between tap and tank are relatively the same.

I know that the stores temperature is the same as the temp in my tank. I would have only had the fish in the bag for about 5 minutes so we can probably rule out temperature shock (I still float the bags regardless). pH I'll be more sure of tomorrow when I'm able to ask them, I'd speculate though that their pH is the same. Something else being in the water really worries me. I've always kept on top of water changes and have taken great care in making sure I wasn't overdosing dechlorinators. Until recently I'd never used meds in the tank, I did place the Prazi in because rather stupidly I panicked, worried that they had internal parasites. I have always run carbon and purigen in the filter because it wouldn't really harm anything by doing so and would act as a safety net. I know they sell heavy metal water test kits, I'm tempted to pick one up and test the water. all of the piping in the street and the house is copper.

The rainbows not being healthy is of course a possibility. Until now I've had great beginners luck in that the worst problem I have ever faced was a fin nipped guppy when I introduced a completely unsuitable fish. That just healed and grew back without my intervention and the offending fish was re-homed. From the outside the Rainbows look perfectly fine, nothing on their body indicates anything is wrong just their behavioural symptoms. I inspected the rainbow that passed away and he looked perfect. In his final hours he was swimming into things almost as if he could no longer see. I saw him swim upside down more than once, he appeared to be physically weak and restless.

Injury again could be a possibility. The only experience I have with this is again with one of my guppies. his pectoral fin was injured when I first purchased them years back. He held the fin close to his body for a couple of days but thankfully regained full use of it. Before with the rainbows, I never noticed them struggling to swim. Like you said before this of course doesn't rule out an internal injury as they're only delicate little beings.

From searching the web I see other people have had the same issues with these fish as I have had (the exact symptoms). A few of them that had water parameters listed were having the same issues even in perfect water so I'm now starting to suspect that these poor souls were doomed from the start. I have noticed that two of them have starting to act a little more normal in the past couple of hours. They're lower down in the tank and are swimming about a little more. I'm really hoping the Rainbows pull through

Edit: ?i forgot to mention that I had done a large water change but didn't notice an improvement.

 

[Kris_H]

Took my pH tester to the store today and they were reading 8.02. I'm getting 8.11 at home so very little difference. Looking at the rainbows they had, some were at the surface others like a couple of mine are and others were lower down. Two of my Rainbows seem to have perked up a bit, but they're still not actively seeking out food. I can see them looking at it when I place it in, they're just not making any effort to get it. I've tried a mixture of foods: JBL spirulina flakes, Fish Science Tropical flakes, Fish Science Tropical granules, Hikari Micro Pellets, Aquarian Tropical Flake, Freeze dried bloodworms, Brine Shrimp and Daphina. I know Dwarf Rainbows are not supposed to be fussy eaters so there is clearly something wrong still. I do see them trying to feed off of leaves, some of them have a tiny amount of diatoms on them.

 

[Byron]

I would not worry about the eating issue, this is not uncommon with newly acquired fish. The fact that they are grazing surfaces means they are looking for food. Once they are settled, they will most likely feed with the other fish.

The fact that you saw similar odd behaviors i the store tank fish suggests this may have been an issue with the fish themselves. Is the store prepared to replace those you lost, assuming theirs survive? This is basic when some of the fish in the store behave as yours that died.

 

[Kris_H]

I would not worry about the eating issue, this is not uncommon with newly acquired fish. The fact that they are grazing surfaces means they are looking for food. Once they are settled, they will most likely feed with the other fish.

The fact that you saw similar odd behaviors i the store tank fish suggests this may have been an issue with the fish themselves. Is the store prepared to replace those you lost, assuming theirs survive? This is basic when some of the fish in the store behave as yours that died.

They offered to replace the one I lost however I declined knowing now that they're unsuitable in my water. I'm just going to hope the four I still have do as well as they can. One of them is acting much more normal now, he even ate flakes for the first time. I was sat in front of the tank for about three hours this evening and noticed one of the Rainbows was intently looking back and following me around. I took some of the flake, submersed it in the water between my fingers and he gobbled a load up. Made my week seeing that .

As it stands only one of them is still glued to the surface of the water. Two are back to hanging around the bog wood like they had done before and one (the fish that is eating) is now quite active and swimming around the tank.

 

[Budy0126]

This will be my first post on this forums, so I hope I can make it count. Although I am fairly new to the hobby in comparison to the other members, I have my own insight that I believe may help you. With the information given (Which is a lot, and helps a lot too) I believe that the fish are either A- Very Stressed or B- have some sort of fungal / bacterial infection.

Let's start with A, which is the more likely of the two. If the fish had just arrived at your lfs when you bought them, it makes sense that they would be very stressed being introduced into your tank. The fish would become stressed from the transportation, the pH change from the breeder to your lfs, and then the pH change from your lfs to your tank. One way to help this it too dim the lights for awhile. If you use a lightboard to provide light, try turning it off for 24-36 hours, and see if the fish improve, or if you use natural light try covering the tank with a blanket. Feed twice a day, but more at night when all the fish are more calm and relaxed, allowing the rainbows to feel safer.

Now to go onto B, which is the less likely of the two. Although you've checked for symptoms of infections, you can never really be too sure. One thing you can try doing is medication the tank. I personally never like medicating the tank, and so there are a few other methods you can try. You can higher the tanks temperature which will kill most infections, or you can also use natural remedies, such as banana leaves or driftwood. One big thing in the hobby is aquarium salt which you can most likely pick up from your lfs (It's natural too)!

Now how did you get here, and how can you stop it from happening again?
CHANGE YOUR ACCLIMATING PROCESS
​

You can never be too safe on how you acclimate your fish, and going overboard is a GOOD thing. I always drip acclimate all my fish, which will allow the fish to easily adjust to your tank's levels. (There are tons of videos and forum posts on drip acclimating) One thing I would do too, is ALWAYS either lower, or turn off your aquarium lights when adding new fish; as this will lessen the chance of your fish becoming overly stressed.

Bests of luck,
-Budy0126

 

[Kris_H]

The fish store keep new arrivals in and off sale for one week before anyone can buy them. The water at the store tested pretty much identically to my own water (I'm am less than a five minute walk away from them). I did 'acclimate' them by placing small amounts of tank water in the bag and taking an equal amount over the course of an hour however I'm under the impression that this practise is a complete waste of time anyway as Byron has pointed out. The parameters between me and the store are all the same anyway, temperature, hardness and pH.

The way these fish were placed in was no different to any of my other fish and they behaved much differently, even to fish that require much softer water to my hard water. I suspect the rainbows had perhaps a minor bacterial infection affecting the gills; them hanging at the surface is one of the hints towards that and is in line with what I've read about these fish from others with the same problem. I never medicate fish, I've honestly found that it does more harm than good. The times I have medicated fish back in my younger years there was a much higher mortality rate than when I simply left fish alone fish in clean water.

New fish will always be stressed, I have done all I can to minimize that like I'm sure most of us will try to do. That includes keeping the lights off for the rest of the day whenever new fish are introduced. I'm sure these fish are no different in that they were extremely stressed when they were introduced to the tank. I've always tried to mitigate this by keeping a tank that's very understocked for its size, maintaining a heavily planted setup that includes floating plants for cover and keeping the water as clear of pollution as it's possible for me to do.

Someone I know is going to be taking the Rainbows if they pull through, along with my Cardinals and Corys. He has softer water than I do at 10dH but still high pH. They'll at least have a much better chance there than they will with my water. I'll keep the Guppies in my bedroom aquarium until they pass on and start selling off all of the aquariums I have. With the water I have and the fish I can get hold of there are so few suitable options that the hobby has been disheartening to say the least!