New Fish Keep Dying!

[jnms]

Last tuesday I got my daughter a 15 litre fish tank.

I've been keeping fish for about 3 years or so myself, had have never had any problem with losing fish.

The 15 litre tank came with its own filter and lighting, we also added in a 25watt heater. I used media from my established tank, which meant that the new filter was fully cycled.

We added in 5 minnows from Pets at Home, 2 of them lasted less than 12 hours the other 3 died 12 hours after that.

Thinking it was poor stock we went to a different shope and got 2 guppys and a Cory from our LFS. The 2 guppys also died in less than 12 hours.

So thinking there must be something up with either the tank, filter or water. I emptied out the tank, scrubbed it with plain water and some vinegar. I also cleaned the filter, heater and thermometer. I then chucked the old media and put another batch in from my established tank.

To eliminate anything else, I left the tank completely bare, i.e. no ornaments or gravel.

We then put another two new guppys in there. That was Saturday, and they have done fine for 48hrs, however now they are starting to look poorly. One lays on the bottom of the tank, and barely moves, the other stays at the surface constantly. The Cory still seems pretty happy.

I am now at a loss as to what the problem could be.

Water stats:
Am: 0.0
Nitrite: 0.0
Nitrate: 10
Ph: 8.0

I am keeping the temp at 26C.

Any help is really appreciated!

 

[BigbruiserAl]

How long has the previous tank been running and how much media are you using?

 

[jnms]

How long has the previous tank been running and how much media are you using?

My old tank has been running for 3 years. I took sponge media out of my Fluval 405 and cut it to the same size as the sponge supplied with the new filter, then used that.

Water quality seems to be perfect, no ammonia or nitrite so the media and filter seem to be doing the job. I am using API liquid test kits.

 

[KittyKat]

For a start, the tank is too small for all the fish you put in there. What were the water parameter readings at the point when the fish died?

Minnows: coolwater (18-20 C is best), active fish, need lots of swimming space.
Guppies: generally unhealthy, weak fish, currently in a stressful environment (bare tank).
Corys: schooling fish, most get too large for a 15 litre tank.

 

[jnms]

For a start, the tank is too small for all the fish you put in there. What were the water parameter readings at the point when the fish died?

Minnows: coolwater (18-20 C is best), active fish, need lots of swimming space.
Guppies: generally unhealthy, weak fish, currently in a stressful environment (bare tank).
Corys: schooling fish, most get too large for a 15 litre tank.

When the Minnows were in the tank there was no heater - however it was a hot day, the tank was at 24C.

The Cory is an Albino Cory - he seems happy. They don't get too big for a 15litre tank, and if it does get too big it can be moved into my 200litre tank. This doesn't explain the current problems.

I agree it could be the bare tank stressing the current guppies, but that doesn't explain the death of the previous fish.

I don't agree that the size of the tank is a problem for 3 fish at their current size.

 

[eaglesaquarium]

pH?

What was your acclimatization like?
What is the water like that they came from (i.e. LFS)?

 

[jnms]

pH?

What was your acclimatization like?
What is the water like that they came from (i.e. LFS)?

Thanks for the reply. Ph is 8.0 as detailed in my original post.

The water from the LFS is the same as ours as the LFS is two roads away from us. And all the fish in my 200litre tank came from the same shop.

I acclimatized the fish in the same way I always do. Float the sealed bag in the tank for 30mins to 1hr, then release them.

 

[Harlequins]

I agreed has mentioned by KK,this tank is too small for the fish you have put in, it stats are spot on then,possible stress on the fishes side or maybe how they were acclimatised??

Albinos has mentioned are shoaling fish and easily reach 3 inches and it you want to teach your daughter about responsible fish keeping then surely either a larger tank or maybe a betta or fish suitable for a 15 litre tank...

I acclimatized the fish in the same way I always do. Float the sealed bag in the tank for 30mins to 1hr, then release them.

Did you add a little tank water every 5-10 mins whilst acclimatising?

 

[jnms]

I agreed has mentioned by KK,this tank is too small for the fish you have put in, it stats are spot on then,possible stress on the fishes side or maybe how they were acclimatised??

I acclimatized the fish in the same way I have acclimatized fish for the past 3 years.

Also, even if the tank was theortically too small and was causing the fish stress, I don't believe that such stress would kill the fish in less than 12 hours.

Did you add a little tank water every 5-10 mins whilst acclimatising?

No. That is not the way I acclimatize; I have never had problems with releasing fish without drip acclimitization. And I successfully keep Discus. Another reason for this is that once the bag is open, the release of CO2 and interchange of O2 causes a jump in Ph within the bagged water which of course makes the ammonia in the bag more toxic.

Thanks for the replies though - any other suggestions?

I mean sure, I can put a Betta in the tank. But I have already lost 7 fish and 2 more look like they may die. I indeed do want to teach my daughter responsible fish keeping and not put anything else in the tank until I have identified the problem. I don't really want to experiment with new fish.

 

[Harlequins]

The whole point of acclimatising fish is to have the fish get use to the water they are going in,temp,hardness ph swings etc etc...just because your lfs is a few streets away doesn't necessarily mean the fish will acclimatise instantly...

Your lfs may have different ph readings to yours,therefore ph shock on fish is a killer.

The volume of water in your 200 litre is a bit different to a 15 litre,and you have been very lucky whilst adding fish in your main tank not to lose any through not adding water when acclimatising.

Just my opinion.

 

[jnms]

The whole point of acclimatising fish is to have the fish get use to the water they are going in,temp,hardness ph swings etc etc...just because your lfs is a few streets away doesn't necessarily mean the fish will acclimatise instantly...

Your lfs may have different ph readings to yours,therefore ph shock on fish is a killer.

The volume of water in your 200 litre is a bit different to a 15 litre,and you have been very lucky whilst adding fish in your main tank not to lose any through not adding water when acclimatising.

Just my opinion.

Thanks Harlequins, but as I already stated in my above post; reason for this is that once the bag is open, the release of CO2 and interchange of O2 causes a jump in Ph within the bagged water which of course makes the ammonia in the bag more toxic.

Drip acclimitization isn't a science. It's a preferance some people have. The problem is that the Ph in the bagged water changes the moment you open the bag. Which can just as easily cause Ph shock, in addition the fish are sitting in their own ammonia at increased toxic levels due to the Ph.

EDIT: Here is some great information on acclimitization: http/www.fishforums.net/index.php?/topic/201084-the-science-behind-acclimitisation/

EDIT 2: Please don't thinking I am knocking your adivice. I'm just stating there are reasons for me not using drip acclimitisation. It's not something random I do, or done out of ignorance. But sure - I can give drip a try, unless someone else comes up with another reason as to why the fish are dying.

 

[marieukxx]

I'm new to the hobby but wanted to try and help if that's ok. You added plenty of mature media and the tests show your tank is cycled so you did all that right. I know you don't normally add water to the bag when you get new fish and flost the bag and this has always worked for you but maybe it's worth giving that a go?

I'd add your decorations back in to the tank. Leave it a few days and then maybe buy a more hardy fish to start off with. Guppies aren't hardy. Platy are hardy fish, maybe get 3.

I would at least try the other way to introduce the fish. Place the sealed bag in there with no lights on for 5 to 10 minutes then after that open it up and add a little of the tank water every 5 to 10 minutes. They say over 30 minutes to an hour. In this case I'd go an hour. And when you release the fish net them and don't add the bag tank water to your tank. leave the light off for another hour at least. It can't hurt to try this can it.

After they are introduced don't feed them anything for a few days.

 

[jnms]

Thanks Marieuk. I am certainly willing to give it a try; only issue I have is that I feel I am experimenting on the new fish - as there's only a chance that it is the acclimitisation causing the problem. If not then the fish will die again.

But the fact the Cory is still alive tells me that it may well be down to the sensitive nature of the Guppies. So trying some platies instead is a very good idea.

 

[BigbruiserAl]

Saying this is the way i have always done it is not helping you as your fish are dying, acclimatising fish does not mean floating them for 30 min despite what has worked in the past...try what people are suggesting or your wasting your own time mate best of luck

 

[coldcazzie]

Agree that guppies are not the most hardy of fish.

I have to say I've done all types of acclimating - bag floating in the tank, just putting the fish straight in, and most recently putting them in a bucket with a slow siphon. Of all the methods I've used, the slow siphon has had the lowest death rate (ie, I have lost none).

While the science behind the reasoning (pH, KH, co2 etc) is good, I think they might be exaggerating how quickly the pH rises once the bag is opened. Even if they were right, there is a difference between the build up of co2 after 24 hours transportation if a fish were ordered online for example, compared to nipping round to your lfs in which case the fish would be in a sealed bag for around half an hour. The amount of co2 built up in that time would not be so high that it would significantly lower the pH, and I doubt the amount of ammonia would have risen so high that it would become immediately lethal were the pH to shoot sky high. I don't think the rise in pH could be accurately described as a "jump".

Even in a planted tank where co2 is injected up to 30ppm (the maximum recommended level before your fish start to show symptoms like gasping at the surface), the pH does not drop so significantly that when you stop injecting the co2 (which is common in many setups - the co2 runs slightly ofset with the lighting) the pH suddenly shoots up and all your fish die of ammonia poisoning. Ok, in a tank like that the ammonia levels will be lower than in a sealed bag, but we are talking amount a small length of time here - as you said - your lfs is only 2 streets away: the fish won't have been in the bag for long enough for several ppm of ammonia to build up, which would be the level at which I would be expecting it to cause death within a few hours.

I'll happily be corrected on this, it's not something I even thought about in terms of science: I use the method that has shown me the best results (as have you, jnms ) but I'm not convinced that their example given is entirely accurate, or that it can reasonably be extrapolated to your situation...