Help!!!

[bobd_uk]

I've recently moved and obviously had to re setup my tank.

Moved all fish to my parents house while I cycled the tank for 4 weeks. After this time, I had ph 6.7, gh 6, kh 4, nitrite 0, ammonia 0.

Put in 12 cardinals. No problems. A week later, put in 5 white widows, 2 ancistrus and a couple of random tetra's. Again, no problem.

On Saturday, (2 weeks after the last set of fish), I put in 2 corys, 2 flying foxes and 3 rummy nose tetra's. Sunday morning, only 1 fox, the ancistrus and corys have survived. Nitrite is suddenly 0.6, having been 0.0 on Sat.

Have done a 50% water change, but nitrite is still at 0.3 and surviving fish are looking decidedly dodgy.

Can anyone help me lower nitrite quickly?

I am running a 48" x 12" x 18" aquarium, with Eheim external filter (containing substrate and floss only). CO2 system has been switched off and replaced with airstone while I try to provide oxygen to the remaining fish.

 

[Cian McLiam]

What did you use to cycle the tank? It wont cycle properly with no fish or other sources of ammonia in it, so adding fish only starts cycling process again.
Salt reduces nitrite damage to fish, but with cories and plecs you cant use it.
If you can, try a nitrazorb pouch or a polyfilter to decrease the levels of nitrite and ammonia, in the mean time, 20-30% water changes daily may be necessary to keep the fish from dying, but be sure to use aged water preferably leaving it overnight and with an airstone in the container.

Ken

 

[bobd_uk]

Cheers. I am using RO water with re-mineraliser - do I still need to age this?