Dear Dhivya Kaviarasu,

Try to do this kind of crystal growth in absence of oxygen by doing this under inert gas such as Nitrogen or Argon to prevent the presence of fungi in your solution.

Dear Talaat I. El-Emary,

Thank you for your idea, but can we add any other chemical which, only destroys the fungus and not react with the solution. Is there any chemical available in that way? because anyway we are going to bring to oxygen atmosphere( for commercial use). there might be a chance of fungus.

add 0.002% sodium azide in your solutions and try.

thank you  Abdul Ajees sir. but  Does it reacts with my solution?

Dear Dhivya Kaviarasu,

As Abdul Ajees mentioned adding 0.002% sodium azide in your solutions may be useful. Please, find in attach a paper on: A STUDY OF THE FUNGISTATIC AND FUNGICIDAL PROPERTIES AND OF THE TOXICITY FOR MICE OF SODIUM AZIDE

by: J. ARTHUR HERRICK AND J. EMERSON KEMPF

Best wishes

thank you dear talaat l. El-Emary.