malc
Aquarium Advice Newbie
Hello all,
I'm having a problem with cardinal tetras in a newly-setup tank. I bought 6 on Saturday, acclimatised them as slowly as possible, and 2 were dead on Sunday morning. Since that didn't leave me enough tetras for a healthy shoal, I bough another six (from the same LFS - which may have been a mistake). Two were dead this morning, and another died this evening.
The second set of tetras were acclimatised to tank water over about 45 minutes (after letting the temperature settle first for about 20 minutes), adding 10ml of tank water every 5-10 minutes until the water in the bag was about 50% tank water.
There's no visible sign of illness on the fish, but every tetra that has died has left the shoal, found a dead spot in the currents in the tank, and stayed there until it died. Three of the dead tetras were white, but two still had strong colour. The dead fish were removed as soon as they were noticed.
To give some background, the tank is a Juwel Vision 180, that has been fishless cycled, and stable for a little over a week. It wasn't really supposed to be used for fish at this stage, but a problem with male guppy aggression (they're convinced one is a female, and keep harassing him) meant that we needed to get some female guppies, and there wasn't room for 12 in the existing small tank (we have 6 males). While picking up the female guppies in a fit of enthusiasm, we also got the first 6 tetras, not realising how delicate they can be. The guppies are all doing fine.
Water parameters look fine to me: Temperature 24.9 (very stable); Ammonia 0, Nitrite 0, Nitrate 5ppm, PH 7.0, kH 5, gH 11, Phosphates 1ppm, O2 5ppm.
The filter is an Eheim 2075, which is too big for this tank (it was actually being cycled for a larger tank), so the flow is throttled back to just under 50%. Outlet is via a spray bar just under the surface on the RH side of the tank, and the inlet is below that near the bottom. There are quite strong currents in the tank. The filter should be around 1450lph, but it's probably nearer 800 right now, as I'm worried that the strong currents are exhausting the tetras.
As mentioned above, there are now 25 fish in the tank; 18 guppies and 7 cardinal tetras. It's also quite heavily planted, with about 20 plants. The water change schedule isn't finalised yet; I did 2 50% water changes over 2 weekends to get the nitrites and nitrates down to where I could measure them at the end of the fishless cycle. It has suffered from brown hair algae, but this was removed by hand as far as possible before the fish were added (and they've been busy eating it ever since...). The gravel (Dorset pea gravel, sad to say) was vacuumed at each water change. So it's still a very new tank, although testing at the end of the fishless cycle suggested it could turn 4ppm ammonia into 10ppm nitrate in less than 18 hours. We've been feeding algae flakes, as that's what the guppies are used to.
I could put this down to a heavily stressed batch of tetras at the LFS, but I'd prefer to make sure that I've not made a stupid mistake (still pretty new to fish keeping) that's been killing the fish. If anyone has any suggestions or advice as to something that might help I'd be very grateful.
Thanks in advance, and sorry for the long post...
I'm having a problem with cardinal tetras in a newly-setup tank. I bought 6 on Saturday, acclimatised them as slowly as possible, and 2 were dead on Sunday morning. Since that didn't leave me enough tetras for a healthy shoal, I bough another six (from the same LFS - which may have been a mistake). Two were dead this morning, and another died this evening.
The second set of tetras were acclimatised to tank water over about 45 minutes (after letting the temperature settle first for about 20 minutes), adding 10ml of tank water every 5-10 minutes until the water in the bag was about 50% tank water.
There's no visible sign of illness on the fish, but every tetra that has died has left the shoal, found a dead spot in the currents in the tank, and stayed there until it died. Three of the dead tetras were white, but two still had strong colour. The dead fish were removed as soon as they were noticed.
To give some background, the tank is a Juwel Vision 180, that has been fishless cycled, and stable for a little over a week. It wasn't really supposed to be used for fish at this stage, but a problem with male guppy aggression (they're convinced one is a female, and keep harassing him) meant that we needed to get some female guppies, and there wasn't room for 12 in the existing small tank (we have 6 males). While picking up the female guppies in a fit of enthusiasm, we also got the first 6 tetras, not realising how delicate they can be. The guppies are all doing fine.
Water parameters look fine to me: Temperature 24.9 (very stable); Ammonia 0, Nitrite 0, Nitrate 5ppm, PH 7.0, kH 5, gH 11, Phosphates 1ppm, O2 5ppm.
The filter is an Eheim 2075, which is too big for this tank (it was actually being cycled for a larger tank), so the flow is throttled back to just under 50%. Outlet is via a spray bar just under the surface on the RH side of the tank, and the inlet is below that near the bottom. There are quite strong currents in the tank. The filter should be around 1450lph, but it's probably nearer 800 right now, as I'm worried that the strong currents are exhausting the tetras.
As mentioned above, there are now 25 fish in the tank; 18 guppies and 7 cardinal tetras. It's also quite heavily planted, with about 20 plants. The water change schedule isn't finalised yet; I did 2 50% water changes over 2 weekends to get the nitrites and nitrates down to where I could measure them at the end of the fishless cycle. It has suffered from brown hair algae, but this was removed by hand as far as possible before the fish were added (and they've been busy eating it ever since...). The gravel (Dorset pea gravel, sad to say) was vacuumed at each water change. So it's still a very new tank, although testing at the end of the fishless cycle suggested it could turn 4ppm ammonia into 10ppm nitrate in less than 18 hours. We've been feeding algae flakes, as that's what the guppies are used to.
I could put this down to a heavily stressed batch of tetras at the LFS, but I'd prefer to make sure that I've not made a stupid mistake (still pretty new to fish keeping) that's been killing the fish. If anyone has any suggestions or advice as to something that might help I'd be very grateful.
Thanks in advance, and sorry for the long post...
