Sand Change, Fish Dying

[bally]

Hi


posted recently with regards to changing the gravel in the tank to sand. I had no choice but to do this with the fish in situ unfortunatly but i was very carefull not to casue to much hassle and stress.


Anywa changed to sand over 3 weeks ago now and in th last week had 3 deaths of my normally strong and bigger fish, my pride and joy clown loach, a sucking loach and one on my 2 blind cave fish which i loved. I have tested the water and all is fine. The fish i would expect to die guppies ect are doing well and breeding. Am worried as to what is going on.Could the sand be casuing a problem with the bigger fish?


Tank is 125lts, made up of mostly guppies now, 2 sucking loach type fish, 1 blind cave fish, 3 britlenose plecs and 1 neon.,oh and 5 or 6 kulli loaches.



Any ideas or anyone come across a problem before with sand

 

[Tizer]

i doubt it would be because if the sand, when you asy your water readings are are fine...what are they exactly?

How big was the clown loach? The tank is too small for them anyway and they are a schooling fish. Could have died from stress i guess from the disruption and none of its own species to ease the stress....but that doesnt really help with the other fish ;/

 

[bally]

not sure what the readings were to be honest. Took the sample to my local shop and he went out the back and tested it for several differant things. He said the PH was a bit high but nothing to overly worry about,,but again didnt say what that was. He said ammonia was not 0ppm but never is,but again nothing to worry about.



the clown loach never grow bigger than about 2" and had him 3 years. He never came out v much.

 

[bally]

just retested my ammonia levels are they are about 0.25

 

[ctsv510]

Took the sample to my local shop.... He said ammonia was not 0ppm but never is,but again nothing to worry about.


the clown loach never grow bigger than about 2" and had him 3 years. He never came out v much.

Ammonia reads 0ppm in a fully cycled tank. If you have 0.25 then your tank isn't cycled, or is going through a mini cycle, so it would be good to know what your nitrite readings were because that can effect your fish too.

And a clown loach that wasn't more than 2" in 3 years was not a healthy fish. It could have been stunted by stress due to lack of companions, being harrassed by other fish, poor water conditions, etc.

 

[TwoTankAmin]

Contrary to what one often sees posted on many fish sites, a decent amount of one's beneficial bacteria lives in the substrate, especially on the surface layer. When you removed all of the gravel and replaced it with sand, you also removed that bacteria and the result was a cycling type spike. What you are measuring now is likely the aftermath. The harm was done soon after you made the switch, not a day or two ago. It just took some time for it to show up as fish deaths.

Ammonia and nitrite levels in a cycled tank should both be 0.