Almost any red safelight that works for your enlarging papers will work for your hand made emulsions. A film emulsion generally has a lower contrast than a paper emulsion by the very nature of things. So, it gains its speed and lower contrast by having a slower addition time of silver to salts. Higher temperatures increase speed and lower gelatin increases speed, but if you go too high in temperature (~80C) or too low in gelatin (~1%) you will get poor results.
Plan on coating your emulsion between 5 and 10% for best results.
Just wondering if you've mixed silver halides formed at different temperatures together?