You can use antibiotic to avoid the growth with no effect on bacteria

You can add chloramphenicol for antibacterial activity and nystatin and griseofulvin for antifungal activity. Good luck

You can use antifungal antibiotics i.e. amphotericin B at 25 µg/mL, MGIT, Nystatin etc.

Hi Kendrick Guevara!

Its depends on your targeted bacteria. Anyway, you may use nystatin at 50 microg per ml (PPM) and cycloheximide at concentration of  100 PPM.

http://aem.asm.org/content/55/3/747.abstract?sid=03eaef42-4ad4-4b87-bf1a-a3b0390e4291

You can also use 100 PPM of cycloheximide.

http://aem.asm.org/content/66/1/206.abstract?sid=5f0825bf-f288-432f-8869-ea4fcfb7bf3e

However, the following articles may also be helpful for you:

http://www.microbiologyresearch.org/docserver/fulltext/micro/38/2/mic-38-2-251.pdf?expires=1522891603&id=id&accname=guest&checksum=CA4C0CB46A3E27F89149A946304D3BBF

http://www.scholarsresearchlibrary.com/articles/formulation-of-alternative-culture-media-for-bacterial-and-fungal-growth.pdf

http://pu.edu.pk/images/journal/impp/PDF-FILES/2-Mycopath.pdf

All the best

Mancozeb is one of the broad spectrum antifungal agent against plant pathogens

Fungi takes about 3 to 5 days to grow, while bacteria grows within 24 to 48 hours. Plating or inoculating your sample on nutrient agar without anti-fungal agent will thus give you bacterial colonies within 24 to 48 hours without the presence of fungal colonies. The plates can even be kept up to 7 days, and no growth of fungi would take place because the bacterial cells have already established themselves and via competition and other mechanisms would prevent the establishment of any fungal cells. However, if you wish to add anti-fungal agent to your nutrient agar you can use Nystatin at a concentration of 100 ug/ml. Note that the agent should be added after your molten agar have cooled to about 50 degree C, if not the anti-fungal agent would be destroyed by heat. Good luck.

nystatin or cyclohexamide

You may add 0.3g/ml Mancozeb

You can add chloramphenicol

i prefer cyclohexamide and chlorramphenicol

You may add 0.3mg/ml Mancozeb

See link below

Article Evolution of bacterial and fungal growth media

nystatitin is very effective

nystatin would work better