The "scale" you talk about is called a VU meter. And if you were to have one for each frequency then you'd have 3 VU meters per channel. On a 4 channel mixer that's 12 VU meters just for channels alone - that's far too much space to be occupied and mostly unnecessary.
I'm not lecturing you on how to DJ or just say "use your ears" but in this case, ensure you have a pair of good quality headphones and monitors if necessary - don't rely on visual aids.
The one VU meter per channel should provide enough of an indication. Cut the mid and high frequencies fully and then the VU meter will represent the low frequency levels.