Fantail Tank set up

Question
Hello,
I have a 5 gallon tank with 3 fantail goldfish with crushed coral.  Is crushed coral a problem with these fish?

THANKS!!!

Answer
Hello Joe-

I've heard bad things about mixing crushed coral and goldfish. Coral and shells are calcium-rich, and this ultimately means that they will cause to pH of the water to rise to dangerous levels. You could try using a 50/50 mix of coral and pea gravel, or just pea gravel alone would be fine.

Hope this helps,
Amber Worman