yesterday i got a small, slightly scrawny guyana ray. i assumed that my water parameters would be ok for him and he has been living happily and feeding well for 24 hours but i just got a shock when i looked at my tap water readings and found out that that nitrate is 40 ppm! as i understand, my ray is not going to stand this for long. i guess he will have to go back to my lfs as they were keeping it in RO/ tap water mix. is this my only option apart from buying a RO unit? WHAT SHOULD I DO????????

