What Could Be The Cause?

[dmanero]

I currently own a 10gallon and a 1gallon tank for the past 3years +. Recently I acquired from a friend a 18 Gallon vertical hexagon tank. This tank is new, it had been empty for a few months, so I have cleaned the glass and rinsed the stones. I had bought a new filtration system and heater for this tank and filled the tank with tap water and allowed it to run with for 48 hours. I've added the water conditioner to make it same for tropical fish.

Now here comes my problem. I have started by just adding guppies to the tank. I bought around 8 small ones. I've noticed that they all swim most of the time on top. Occasionally they on the bottom and basically dive down and one at a time they dive up. I thought it could be a lack of oxygen so I've added a air stone in to the tank. But I have see no change. they still swim near to the top. Also 2 fish has died within 48 hours. I've set the temp to 26C. Is this too high?

Can anyone provide me with any answers. Is this normal for guppies to swim like this? Is there anything I can do to the tank to make it better suited to hold fish. Any information would be greatly appreciated.

 

[denzil1nil]

check out the video link by rossc in the thread 'what first? live plants or fish first?'.

 

[dmanero]

Can any one say how warm the thermostatic should be set at. As I said it's 18 gallons and I have it set right now at 28degrees celcius. is that too high?

 

[rousell]

You need to cycle your tank. There's loads if information available on this forum.
Here's some info about the guppies;

Common Name: Guppy
Scientific Name: Poecilia reticulata
Origin: Central North America to Brazil
Maximum Size: 2 inch
Care: This fish is very easy to care for, they are a pretty hardy species and can tolerate a variety of water conditions, but prefer slightly alkaline water. Temperature should be 68-79° (degrees) Fahrenheit. The minimum tank size is 5 gallons.
Feeding: Be sure to provide a variety of foods, preferably live ones, because a nutritious, complete diet will enhance their colors and ensure good health. Keep in mind that they will eat their young if they are small enough.
Breeding: These fish are very easy to breed and they are able to have a batch of fry every 28 days. A pregnant female can be identified by the gravid spot (darkened area) behind her anal fin. An average brood is average is 40 to 50 babies.
Sexing: The females are bigger than the males, the males are much more intensely coloured than the females. Males have a gonopodium. - See the article for explanation of gonopodium.
Comments: Guppies live only about two years. There are many many different colour and fin combinations available. It is advised to keep two or three females to every one male to prevent the males fighting it out between each other.

 

[fluttermoth]

That is a bit high for guppies; 23/24°C would be better.

The immediate problem is most likely ammonia poisoning, from being in a tank without a mature/cycled filter (ie, one that doesn't have the necessary bacteria colonies to remove ammonia and nitrite from the water, turning them into the relatively harmless nitrate).

You'll need to do a lot of large water changes to keep the ammonia and nitrite down until those bacteria grow; you might be able to help the cycle along if you can add some already mature media to the filter from another of your tanks, if they're still running with fish in, and as long as the filters haven't been cleaned under the tap.

There are good articles on the nitrogen cycle, and fish in cycling, in the beginner's resource centre; the link for that is in my sig.

 

[JL94x4]

To me, ive always gone by, if any fish are on the surface, and the tanks well oxygenated, its most definatly, amonia/nitrate and this is a sign you need to do a test.

 

[`Peter]

Need to cycle tank fish are near the top because of higher ammonia levels which makes it harder for them to breathe.