Help needed please

Hi everyone can someone help please

My girls are 5 weeks old just started to bud
Grown under 300w true watt approx mars hydro, grown in biobizz light mix
Using the fox farm trio nutes

They were showing signs of nitrogen toxicity so I have flushed them today using plain ph'd water

Now that there's no nutrients in the soil when do I use nutes again please n how much nutes do I use

I tried to give 1/4 strength about a week ago didn't read it correctly due to bein tired

Any advice would be appreciated, the girls look quite happy but we're getting slightly worse each day

Thanks guys

Any pictures will help people diagnose your problem for you