Unfortunately bro, being in your fathers position, it would be very hard to "naturally" increase his test levels. A good idea is to maybe start him on some Proviron(mesterolone) first. It's an oral and it usually, depending on the manufacture, starts at a dose of 25mg or 50mg a pill. It's easy to take and Proviron actually increases sexual desire and is extremely effective in producing strong erections. And another good note to add is that it kind of gives you a natural "feel good" sense about you. I'm not disagreeing with any of the above statements as I agree full-heartily with what there saying about maybe starting him on a low dose of Test E or C. But I honestly would have him try Proviron and see if he likes it.
Here's a good description of it, if you're not sure what it is...
Proviron
Product Description:
Mesterolone is an oral anabolic steroid of the generic compound mesterolone , but behaves as an anti-aromatase agent therefore, Mesterolone is classed as an androgenic steroid and anti-aromatization prescription product.
Mesterolone is the closest substance we have to by mouth active Dihydrotestosterone (DHT). It is basically methylated (1-methyl) DHT. As a result, Mesterolone isn't able to metabolize(aromatised) into oestrogen, and it is not progestenic as well. It is in reality pretty light on the liver, and not very toxic at all, as it's not c17-Alpha-Alkylated, but it is 1-methylated. Naturally, being a DHT-based compound, this substance Is not going to be good for female person (athletes) to apply in high dosages, although from interviews with females, 12,5 - 25 mgs per day seems to be really tolerable.
Indications:
Mesterolone is generally thought of as a tempering agent, and as being not very anabolic on its own.
A really engrossing truth about Mesterolone is that it concatenates very well to SHBG (Sex Hormone Binding Globulin) which is the transport hormone responsible for cutting down the quantity of circulating free testosterone in your body. It actually concatenates to SHBG better than nearly any other anabolic steroid. Proviron also concatenates to the Anabolic Receptor (AR) better than any commercially usable oral anabolic.
Thus what we have here is a steroid which can potentially make other steroids more effective by inhibiting SHBG from attaching to them, and it has the extra profit of cutting down the quantity of overall estrogen in the body as well. It is not the sort of steroid that we can base a cycle around, but those attributes sure make it advantageous for adding it into virtually any cycle. This of course offers a hard, quality look to muscle too that’s gained on a cycle, and an overall advance in the look of the physique. Besides, up to 100-150 mgs per day it has no depressing effect on low to normal serum FSH and LH levels. In point of fact, if your natural hormonal levels are depressed, it can even help increase LH, which can then increase your natural testosterone levels.