Bottom Half Of Tank

[chesterben]

Hi,

I have a Jewel 70 with a variety of fish. All is well generally, however the fish only appear to stay in the bottom half of the tank when the light is on (15W).

I have noticed that when it goes off the fish almost instantly swim to the top.

I have mostly tetra type fish (Neons etc) as well as a few loaches.

Does anybody have any idea?

Thanks

 

[Noahs ark6]

Light might be too strong

 

[KittyKat]

If the light was too strong, the fish would swim down.

Can you post a full stock list? How often do you feed? They might just associate light with food.

 

[fluttermoth]

I doubt very much if any fish would find a 15w light too strong!

Most tetras and certainly the loaches do swim in the lower levels of the tank normally anyway.

I'm not sure why they swim up when you put the lights out though...Kitty Kat may have a point; I often feed my fish when I put the light on so they see that as a signal and tend to swarm upwards; they may just be reacting to you coming over to the tank (unless your lights are on a timer)

 

[chesterben]

If the light was too strong, the fish would swim down.

Can you post a full stock list? How often do you feed? They might just associate light with food.

Yeah this is what they do, swim to the bottom when the light is on.

I have just tried covering up most of the lamp so the light is greatly reduced. At the moment they still seem to be staying at the bottom.

 

[chesterben]

I have attached a photo.

You can see them close to the bottom. The light is on a timer and I tend to feed them before the light comes on.

 

[jpeterson]

Can you post your water stats please?

pH?
Ammonia?
Nitrites?
Nitrates?

Stock list?

 

[fluttermoth]

It would be very useful to have some water stats if you have them.

Having said that, I think I know what your problem is now you've posted a pic; I think it's that your fish feel too exposed in the top half of your tank. Small fish like Neons like to have lots of hiding places; paradoxically, the more hiding places you have, the more the fish will be out and about as they know they have somewhere nearby to swim to if a predator comes along. You and I know there are no predators in your tank, but the fish don't!

If you could get some taller plants and some kind of backing for your tank I'm sure that would help.

 

[chesterben]

It would be very useful to have some water stats if you have them.

Having said that, I think I know what your problem is now you've posted a pic; I think it's that your fish feel too exposed in the top half of your tank. Small fish like Neons like to have lots of hiding places; paradoxically, the more hiding places you have, the more the fish will be out and about as they know they have somewhere nearby to swim to if a predator comes along. You and I know there are no predators in your tank, but the fish don't!

If you could get some taller plants and some kind of backing for your tank I'm sure that would help.

Hey thanks for that, I will give that a go. To be honest I don't know the stats, I just do partial water changes on a regular basis and they seem healthy enough (fingers crossed).

 

[KittyKat]

The above is correct.

 

[chesterben]

I have tried the above, added tall plants and put backing on. However it does not appear to have made much of a difference. They still appear to move to the bottom as soon as the light comes on, and conversely they move to the top once it goes off.

Any other ideas? Or can it take time for them to re-adjust to the new environment?

 

[Timmy_Bee]

could it be too hot? and the light is adding to the heat? what temp is your tank

 

[chesterben]

could it be too hot? and the light is adding to the heat? what temp is your tank

I dont think so, it was at the lower band (21 I think) but I turned it up slightly to see if it may be been too cold!

My stock is : -

4 x Neons
5 x Black Neon Tetra
3 x Harlequins
4 x Scissortail Rasbora
5 x Loach
3 x Shrimp

 

[Lolly123]

I would invest in a decent liquid test kit if you dont have one already, it's always a good thing to know what the stats are even if your tank 'looks' fine. You never know when you might need them.

 

[chesterben]

I would invest in a decent liquid test kit if you dont have one already, it's always a good thing to know what the stats are even if your tank 'looks' fine. You never know when you might need them.

I would but I still dont understand why it would change when the light goes off! The bulb is one of those that looks pinkish and brings out the colours of the fish, could this be the problem?