First Loss - Nitrite Still High

[mobeyone]

Following on from this thread one of my corys has just died.

Carried out yet another 50% water change and the following readings have been taken:

pH: 6.6
amm: 0
nitrite: 2.0

I just cannot get the nitrite to go down.

I "washed" the filter out in the old tank water, just a slight dip in the old water and placed back in as it is starting to get very mucky but I am one cory down now and panicking.

I have a 90l tank currently 5 weeks or so old with the following:

5x neon tetra
1x plec
3x cory
2x silver shark
2x gouramis

I am scared of losing the lot now.

Water is crystal clean, very miminal waster came out of this cycle and the gravel is all clear. Temp is stable at 75 and water change was carried out with 2x boiled kettled water with a hose. Water treated with cycle and aqua plus.

Should I try a product which reduces nitrite?

Tap water is ok.

Also, my filter looks like its slowed down??? sounds awfully quiet?

 

[WILDER]

How long has the tank been set up, sounds like your filter not coping with the load.
How big are the silver bala sharks they grow big and need massive tanks of 120 gallons.
What filter are you using and how many gallons does it turn over in an hour.

 

[mobeyone]

Tank has been set up for around 5 weeks or so now.

Filter is a fluval 2, not sure about how many gallons it turns over?

As for the sharks, both are small, less than an inch or so.

 

[WILDER]

Seen the probelm straight away filter not good enough.
Buy another fluval 2 transfer one of the old sponges into the new one and put a new filter sponge back into the old one.
I would rehome the bala sharks the tank is to small.
If you don't want two filters running get a filter twice the turn over of the gallons.
If you rehome the sharks you could get away with a fluval 3 not sure if a fluval 4 would fit in your tank unless you check.

 

[WILDER]

Need to clean the impellor if the filter slowed down.
Always best to over filter a tank, I find the fluval 2 does not do a very good job in that size tank even though it does state its fine on this chart, but they are not, a fluval 3 to four if you keep the right fish in the tank.
Technical Specifications

Model Item # Output Watts Aquarium Size
L/H US gph
Fluval 1 Plus A -160 200 50 5 Up to 45 litres
Fluval 2 Plus A -165 400 105 6 90 litres
Fluval 3 Plus A -170 700 185 6 130 litres
Fluval 4 Plus A -175 1000 260 10 215 litres

 

[mobeyone]

Seen the probelm straight away filter not good enough.
Buy another fluval 2 transfer one of the old sponges into the new one and put a new filter sponge back into the old one.
I would rehome the bala sharks the tank is to small.
If you don't want two filters running get a filter twice the turn over of the gallons.
If you rehome the sharks you could get away with a fluval 3 not sure if a fluval 4 would fit in your tank unless you check.

Went into the local lfs and they advised my filter is more than adequate??? I may buy a second one but I bought nitrazorb today after speaking to one of the lads who is very good and is very confident etc.

I have placed nitrazorb in the filter, removed the carbon and one of the white ones and placed the nitrazorb into the filter.

Filter is working much much better today and another 30% water change has been carried out.

One more tetra has since sadly passed away but after discussing I think the deaths are down to the filter and not the water??

The sharks will be rehomed but I have been told that they should not outgrow the tank?

Also, the impellor is clean and clutter free. The filter inside was clogged at the top with a brown slime.

I have placed the carbon filter and a white one to stand in tank water, is this ok?

Thanks for your help.

 

[mobeyone]

Another 30% water change.. and the nitrazorb looks like its working!

results:
nitrite: 0.50/25
ph: 6.4/6
amm: 0

Anyone have any advice on how long I should use the nitrazorb for? and when I should reintroduce the other filters I took out?

 

[WILDER]

The sharks will be rehomed but I have been told that they should not outgrow the tank?
I can't believe they have said that, the fish will suffer as it will get stunted growth.
If you rehome them now no problem, but if you kept them they will die.
The filter fine if you have small tetra fish in that size tank, but not with the stock you have.
I always get a better filter for a tank, and it keeps my water crystal clear as it pulling more volume of water in.

 

[rowdyburns21]

Seen the probelm straight away filter not good enough.
Buy another fluval 2 transfer one of the old sponges into the new one and put a new filter sponge back into the old one.
I would rehome the bala sharks the tank is to small.
If you don't want two filters running get a filter twice the turn over of the gallons.
If you rehome the sharks you could get away with a fluval 3 not sure if a fluval 4 would fit in your tank unless you check.

Went into the local lfs and they advised my filter is more than adequate??? I may buy a second one but I bought nitrazorb today after speaking to one of the lads who is very good and is very confident etc.

I have placed nitrazorb in the filter, removed the carbon and one of the white ones and placed the nitrazorb into the filter.

Filter is working much much better today and another 30% water change has been carried out.

One more tetra has since sadly passed away but after discussing I think the deaths are down to the filter and not the water??

The sharks will be rehomed but I have been told that they should not outgrow the tank?

Also, the impellor is clean and clutter free. The filter inside was clogged at the top with a brown slime.

I have placed the carbon filter and a white one to stand in tank water, is this ok?

Thanks for your help.

Nitrazorb sounds like a product that gets rid of nitrate to me!!!
The filter is not failing you are just cycling and heavily stocked.
Keep up the water changes thats all you can do

 

[WILDER]

With the stock she has in that small tank I would of expected it to be cycled by now after five weeks.
Or its the filter not coping like I have said if this is the case she will never cycle.
What is your tap nitrate reading.

 

[WILDER]

You should never touch your sponges in a cycling tank.
No need to touch them sponges for at least six months, you go by your readings.
Only time you touch your sponges is high nitrate readings and there blodged up with loads of brown mess.

 

[rowdyburns21]

With the stock she has in that small tank I would of expected it to be cycled by now after five weeks.
Or its the filter not coping like I have said if this is the case she will never cycle.
What is your tap nitrate reading.

Im still under the impression it is cycling, the only reason I think the filter is coping is because there is no low level ammonia, high nitrite is the last week of your cycle

 

[mobeyone]

I am inclined to agree with rowdyburns here, ammonia and ph have all been managed down with water changes but nitrite has remained high.

The filter had loads of brown mucky stuff at the top which I think clogged up the filter and stopped it from working as the water was just trickling out for nearly a day and this I think has led to the two deaths.

I think I may have introduced to many fishes in the week before last as all was fine before this.. and the nitrite just went sky high.

Nitrazorb seems to be working! and all is lookimg ok, I was advised by the lfs that it maybe some time before nitire comes down but to conwith just 30% water changes for the time being.

 

[WILDER]

I'm sorry but if a filter has blocked up that fast in a cycling tank and the sponges look block up with brown muck, the filter not coping.Yes the filter fine for the tank size but it all depends on how you stock your tank as some fish produce more waste than others.By the way you have a plec and they are massive waste producers, have you ever done a vac of the substrate.

 

[WILDER]

Post water stats in ammonia,nitrite,nitrate,and ph.
Need tap nitrate reading.