Hey guys,

Some background about me first:
I am 25 year old male
I am 5' 9-3/4" and weigh 150 lbs
I work out 6 days a week, with 2-3 days of cardio and 2-3 days of lifting
On my cardio days I generally run between 4-6 miles in under 45-50 mins easy, I don't really clock myself since I'm just doing it for the health and enjoyment of it...
I lift by focusing on muscle groups and will throw in ab work outs every day I lift...
I eat what I consider a healthy balanced diet, which is high in protein, good amount of Omega-3 fats, very low saturated fats, good carbs for energy and I eat small meals every 3-4 hours, I get lots of fruits and veggies and drink only water and some gatorade (g2) for added electrolytes...
I tested my BF with an Bio Electric Body fat Impudence tester and it rated me at approx 7.8%...I had others use it who do not work out much just to make sure it was working and these guys ranged between 18-30%...so I suppose it is.

I know that genetics play a role in having defined abs and muscles, but there HAS to be a way to beat this...(please!)...I have no ab definition and my muscles are really not "ripped" I know people with higher BF on the same scale that have great definition.

I hear that under 10% is a good rating, I will back this up with a caliper reading for my BF when I get a chance to find someone that knows how to do that properly for me, but in the mean time I am asking...
What am I doing wrong?
Is it possible that some people might never have muscle definition even at say 5% BF?
Would it even be healthy for me to go as low as 5% and below?
I have been working out consistently for only about 5-6 months, I have become leaner, but I seriously look more like I have 13-15% BF.

if only I had better genes for this *sigh*

those BF testers aren't accurate I'm afraid. with your height and weight, you're probably not fat, so I'd just focus on adding some muscle if I were you.

Maybe you need to eat some more calories in order to gain some size?