We usually add 20 mg/L.

just use 20 mg/l benomyl after autoclave. remove all fungal contamination.

I have experiences with even higher doses of cycloheximide (100 - 500 mg/L), but not all fungi are sensitive to cycloheximide, some of them are resistant (usually dermatophytes or some saprotrophic). Use of benomyl or nistatin may help, but no antifungals work on 100%.

You might want to give nystatin a go:) I have always use it for fungus. Cycloheximide can help eliminate all other eukaryotic algae but I find that it was not so effective for fungus (I have tried using concentrations from 100-400mg/L). So, I second the above comment:)  

Mycostatin Nistatin, are good options for controlling fungi, which you will not kill with the eucaryotic protein synthesis inhibitor cycloheximide.  Also consider a gram positive bacterial inhibitor to clean out these bacteria.  Cheers...

Kindly Dr.Paul v zimba 

What is the suitable concentration of myostatin in BG11 media please

Many thanks 

I would add three or 4 concentrations start with 5 mg/L then 10, then 20, then 30 mg

Many thanks  Dr. Paul v zimba.  I will follow your advice 

I have added 50 mg/L of cyclohexamide to previne green algae contamination and fungal growth as well.

I have already used higher doses of cycloheximide (500 mg/L). This concentration is sufficient to suppress all contaminant fungi and yeast. However, some fungi are resistant (dermatophytes, some yeast specially candida albicans ) .

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We are using cycloheximide at the concentration of 500 mg in one liter of the medium since 1973. It will inhibit the growth of many fast growing .fungi. However, dermatophytes are resistant to cycloheximide.