Fish Deaths

[cartandpeg]

Hi All,
I have had my aquarium up and running for about two and half months now,the tank cycled ok and fish added where going along fine.

About three weeks ago the stocking was 20 neon tetras,6 bronze corydoras and 10 rummy nosed tetras and 4 red cherry shrimp.

I did my normal water change 3 weeks ago and within the next three days I lost 8 neons,3 bronze corydoras and 7 rummy nose tetras.I change between 30 and 45 ltrs per week along with a vacuum of the sand.

Since then I have lost another 4 neons and I added another 9 rummy nose tetras two days ago and have lost 2 of them,with another 2 rummies and 2 neons not looking the best.

The only species looking good are the shrimp.

I have done nothing out of the normal during water changes,the only thing different was I switched to Seachem Prime,which when added was to per instructions.

I checked the water during the huge die off and all was good,using a new API Master test kit.

I just checked the water again and readings are:

Ammonia 0
Nitrate 0
Nitrite 0
PH 6.8
Temp 80 F.

I feed once daily with either shrimp pellets or frozen blood worms which are defrosted before going into the tank,I also drain any water residue left from the frozen blood worms prior to feeding.I do not over feed.

I have noticed that I am getting some black beard algae starting to grow on my anubias plants and on the rocks.

The tank is 240 ltrs with a trickle filter system doing 1000 ltrs per hr and a 1500 ltr per hr wave maker to circulate the water,the tank is not in any sunlight as no sun shines on that side of the house.

The lights are on about 6 to 8 hrs per day,which are 2 x 30w and 1 x 25w all tubes are T8.

The tank has sand substrate and planted with wisteria and some twisted vallisneria and anubias on the golden vine driftwood.

Filter media is rinsed in water from the tank and only portions are replaced when they are just to dirty to use again.

Any clues please.

Thank you.

 

[N0body Of The Goat]

30-45l weekly water changes on a 240l is not enough, you should be aiming for 120l (~50%) without fail. If doing this is one go is overwhelming, remove ~50% of the water one day and then add new water over a number of days, for instance 20l per day (I have to use this approach with my Halfbeaks because they are extremely sensitive to water chemistry changes).

Bloodworm should not be treated as a staple diet for your fish, yes they love them, but they are nutritionally poor and that is not good for young fish purchased from a LFS. A once weekly treat is ample. A varied diet is the best approach, you are then more likely to provide the wide range of nutrients your fish need to stay healthy and reach their potential adult size.

Why the 80F (~28C) temp? That is far too high for Neon Tetras and Bronze Corydoras, while at the high end of the range for Rummynose too. Warmer water raises metabolism and lowers potential oxygen levels.

If fish are dying and you have no definite diagnosis and cure, you do not go out and buy more fish, end of. I had a scare in my 5x2x2 mid summer, nothing came in or out of that tank for 2 months, it went into quarantine lockdown.

Rummynose are good visible signs of how the water quality is, if they do not have vivid red noses, it is time to act and do a large water change.

How hard is your tank water? You should have something in the 5-10gH ballpark with your choice of fish, softer than my water but enough buffering capacity to prevent a pH crash.

How did you cycle the tank? To what concentration of ammonia were you dosing? Did you do a "qualifying week"?

Overall I'd say your stocking levels are risky for what appears to be a brand new tank/filter setup. A mature setup might cope with 36 fish added in quick succession, but not a newly cycled filter. Your inital stocking was ~140cm of adult fish, which is considered high verging on overstocked, especially when you consider you have lost something like 20-40l of water volume to sand/bogwood/ornaments etc. in your 240l. Plus there is no escape from the fact that Neon and Rummynose Tetras have a notorius reputation for fatailities in immature tanks.

Personally, I would do what I call an "emergency water change", removing 80-95% of the water and refilling gradually during the day (turning the filter on as soon as possible).

 

[scotty]

also what is the temp of the water you are adding to the tank at waterchanges,i had a disaster in the summer where the water i added was way too cold(children and hoses don't mix very well) and i lost a lot of fish due to the sudden change in temp.

 

[phoenixgsd]

im curious why you dont have any nitrate? i thought all cycled tanks had some

 

[cartandpeg]

Thank you for the replies,
After reading the replies the guilts are now becoming obvious.

Dropping the temp is no problem along with far greater volume of water change.Unfortunately it is 11.05pm here and to do an emergency change now is really not feasible.So up and at em first thing in the morning.

Hardness of the tank water is something i could not tell you,so I will look into getting a kit to test that asap.

The cycling of the tank was done not with ammonia,can not buy it here,only cloudy ammonia,hence thats why I never went down that path to cycle the tank.

Basically I took all the filter media,substrate and plants from a established tank and transfered them into the new tank,this ran for about a week,I had a major problem with the tank with the fish in and put them into the new tank.

That was one mistake,plus the overstocking.As I was getting good water readings I assumed it had cycled with the established filter media etc and the fish would be ok.

When I did do the water change where I lost most of the fish,I will admit that the water that went in was of higher temp than the actual tank temp,I can not blame the wife for that as she done the new water for me and I did notice the temp difference and should have corrected it there and then,but ( no excuse really) it was a hasty water change as every thing sort of went pear shaped that day and I needed to get the water change done and get to where I should have been half hr before.

So in hindsight it was my mistake and even though circumstances where against me,I should have looked at another alternative at the time of introducing the fish into the new tank.

So I will not put any more fish in and put the tank in quarantine lockdown and do a major water change.

Thank you again for info to you both,a lesson learnt for me.

In reply to phoenixgsd,if that is the case of an established tank having nitrate readings,then I have jumped the gun and basically running a not correctly cycled tank.

Thank you.

 

[phoenixgsd]

The cycling of the tank was done not with ammonia,can not buy it here,only cloudy ammonia,hence thats why I never went down that path to cycle the tank.

Basically I took all the filter media,substrate and plants from a established tank and transfered them into the new tank,this ran for about a week,I had a major problem with the tank with the fish in and put them into the new tank.

at a guess, all the media you took from the estabished tank should have been sufficient, however, did you run the tank for the week without fish? this would starve the bacteria in the media, hence starting another cycle, the bacteria need a ammonia source (fish poo) to feed from

 

[cartandpeg]

I think I ran the tank for about 3 maybe 4 days,then I put in two algae eaters.

 

[PlumbersMerchant]

ive always seemed lucky with that side of things. My tank is set up at 26 degrees C, i do 1/3 water change each month (obviously if when doing weekly water tests a change is required sooner then i will do) Ive had my tank for a year now so everything seems to have settled weel (TOuch wood)

Hope you found the answers to your questions