First grow GDP Auto

Germinated- 1/18/20 2GDP Auto and Sour 60 only 2 out of the 4 germinated and that was both the GDP Used 50/50 ocean forest and happy frog with 20% Perlite. I was having humidity issues the first couple days during sprouting, maybe 40% the first 3 days or so. MY humidifier came in and it now floats between 55-60. Lights are HLG 3500 spec. I didnt flush my soil prior to placing my seeds in the soil, i took a reading today and my soil is 5.6 so any tips on how to raise this will be nice.