Stocking density, feeding and nitrites (long!)

[rbel]

We have recently been given a 240 litre (63 US gallon) Juwel tank already stocked with the following:

2 Golden Barb
2 Green? Catfish (Brochis splendens)
2 Bristle nose Catfish
2 Glass Catfish
1 Silver Hatchet
1 Kribensis
3 Clown Loach
1 Bleeding Heart Tetra
2 Cinnamon? Tetra
2 Congo Tetra
6 Lemon Tetra
1 Neon Tetra
2 Hockey stick (Penguin)? Tetra
3 small unidentified fish

As far as we can determine from using a tank surface area calculation this population is around the maximum stocking density – grateful for any comment on this.

We have two problems:

a) Establishing what the correct amount of food should be
b) Dealing with an apparent nitrite excess

We were told by the previous owners to feed twice a day a mixture of flake and granules but as the result of a nitrite spike (>5 mg/L) this has been cut to a single daily feed of a small amount of flake and a few catfish pellets. The flake appears to be consumed within two minutes by all but the Bristle nose and Brochis catfish and the loaches, but the pellets tend to hang around for some time.

The water seems to be staying fairly steady at:

pH 6.8
Ammonia 0.5 mg/L
Nitrite 0.5 mg/L
Nitrate 25 mg/L
25C/77F

The test kit that came with the tank is a fairly recent API Master Test Kit.

We appreciate that the nitrite level should be 0 and have been carrying out 12.5% water changes every day (2 x 30% changes on the two days after the >5 mg/L spike was noticed) but the nitrite level appears to be ‘stuck’ at the moment.

In general this fish appear (to our inexpert eyes) to be active and healthy with the possible exception of the 2 Hockey stick tetras and the elderly Neon tetra who do, from time to time, exhibit a noticeably high respiration rate – a water change and some additional aeration seems to help overcome this.

Grateful for any advice on the stocking density, feeding and nitrite issues.

rbel

 

[budrecki]

We have recently been given a 240 litre (63 US gallon) Juwel tank already stocked with the following:

2 Golden Barb
2 Green? Catfish (Brochis splendens)
2 Bristle nose Catfish
2 Glass Catfish
1 Silver Hatchet
1 Kribensis
3 Clown Loach
1 Bleeding Heart Tetra
2 Cinnamon? Tetra
2 Congo Tetra
6 Lemon Tetra
1 Neon Tetra
2 Hockey stick (Penguin)? Tetra
3 small unidentified fish

As far as we can determine from using a tank surface area calculation this population is around the maximum stocking density – grateful for any comment on this.

You are severely over stocked (I will post late with specifics and how to correct this)

We were told by the previous owners to feed twice a day a mixture of flake and granules

Once a day feeding is fine. You can feed twice a day, sparingly, if you choose to.

The water seems to be staying fairly steady at:

pH 6.8
Ammonia 0.5 mg/L
Nitrite 0.5 mg/L
Nitrate 25 mg/L
25C/77F

You should be reading ammonia and nitrite of ZERO....your tank is going through a mini cycle, mostly due to stocking levels.

We appreciate that the nitrite level should be 0 and have been carrying out 12.5% water changes every day (2 x 30% changes on the two days after the >5 mg/L spike was noticed)

You should be changing as much water as necessary to bring the ammonia and nitrite to zero. 50%, 75%, what ever it takes. Water changes are your friend!

but the nitrite level appears to be ‘stuck’ at the moment.

The cycle again...are you familiar with the cycle?

 

[RISK2123]

it sounds like you kinda know what your doing but ill just shoot out maybe a couple suggestions and questions..

what type of filter are you using?
those tetras are pretty small so they dont have a large contribution to waste. but that is quite a load of fish in your tank. i would say its possible to get away with all those fish but you would need some serious filtration and keep up with the water changes. but really its just probably better to just bring some fish back to your lfs or sell them.

doing small water changes as you are is definately helping the situation and i would suggest keeping to that stratagy untill things settle down a little. but i would also recommend doing one large water change (around 60-70%) tonight or whenever you have a chance, then the next day continue with the testing and small water changes.

how long has the tank been setup with all of your fish in it?

 

[budrecki]

OK, so yo have a 63 US gallon tank

I've listed the fish and the individual issues.....

2 Golden Barb- like all barbs, these are schooling fish...they need to be in a school
2 EMERALD CORYS -like all corys, these are schooling fish...they need to be in a school
2 Bristle nose Catfish- (bristle nose plecos) ok fine
2 Glass Catfish- :huh: need to google this one
1 Silver Hatchet-needs a school
1 Kribensis-the lone cichlid..I'd find him a new home
3 Clown Loach-gotta go! needs a school and cannot grow to a normal size in a 63g tank (180g minimum)
1 Bleeding Heart Tetra-needs a school
2 Cinnamon? Tetra-needs a school
2 Congo Tetra-needs a school
6 Lemon Tetra- (YEAH! A SCHOOL!) perfect!
1 Neon Tetra- needs a school
2 Hockey stick (Penguin)? Tetra-needs a school
3 small unidentified fish-hmmmmmm


A school is generally accepted to be a group of 7+ fish. The more fish in the school, the happier the fish and the better the schooling behavior.

You're going to have to make some choices if you want these fish to have the best possible life. You tank size cannot accommodate schools of each variety that you currently have.

 

[rbel]

RISK2123 - The filter is the Standard H internal Juwel 600 litres per hour mechanical/biological filter (see http://www.juwel-aquarium.de/en/aktuelle_modelle303.htm?cat=77 for further details).

The tank has been set up for some years and the majority of its inhabitants are one or more years old. Ten days ago the fish and water were carefully removed and all the kit moved a hundred yards to our property where it was set up again, using the existing water, filter etc. We retained the substrate (which had just been cleaned) but removed the existing 'decor' and added a Juwel modular background, and new rocks, prepared hardwood root pieces and new plants from a reputable LFS. No new fish have been added.

 

[budrecki]

Gravel can contain quite a bit of your biological filter. It looks like in the process of moving and cleaning the gravel the biologic filter has been compromised.

This does not negate your stocking issues.

 

[rbel]

Budrecki - thank you for your explanation of the need for the majority of the fish to kept in schools. I think it unlikely that we are going to be able to resolve this particular problem in the next few days. I appreciate from your posts above that, in your opinion, there is a need to reduce the overall stocking density as a priority - by how many fish?

 

[RISK2123]

Gravel can contain quite a bit of your biological filter. It looks like in the process of moving and cleaning the gravel the biologic filter has been compromised.

This does not negate your stocking issues.

ill have to agree all around in that statement. do you have another tank already setup or is this your only one?

 

[rbel]

RISK2123 - this is our only tank (we are completly new to keeping fish)

NB Closing down now - it is 1 a.m. in the UK

 

[RISK2123]

well goodnight!
and for when you get up...
some stress zyme may benefit your tank due to the loss of so much of the biological filtration. i would dose per instructions for about 5 days. if you are considering getting rid of some fish i think the best bet would be to tell us which species of fish, that you already own, is your favorite. everybody has different opinions on a "cool" or "nice" fish so i think thats your call and we can go from there...