Bloodfin Tetra's

[Iggy monster]

i have 4 tetra's 2 male and 2 female, now the female will just loose all their colour for no reason and then couple of hours later it comes back. i have tested all my levels which are perfect. Tempature is on par. i read online that it is common for the females to loose the colour when they want to breed, and then after breeding get thier colour back. They look healthy, swim and play, also eat. What could also factor them loosing thier colour?

 

[Andrew McFadden]

Stress from being picked on could cause it as well

 

[Iggy monster]

what kind of sand should i use for bloodfin and a bala shark? i like the look of sand better than rocks.

 

[Andrew McFadden]

Play sand
General purpose sand
Blasting sand
Pool filter sand
Sand sold at pet shops