What is the proper smell of Basa? I buy basa frozen (note, not the same as bass). It's not something readily available here but I like it because it's affordable and easy to prepare.

I go through the appropriate steps of fish prep by defrosting it in the fridge and rinsing the filets before use. 

I've made it in many different ways and even purchased it from different places but my husband says it still tastes strongly of mold. I can't taste that in it at all. 

Is there something I'm doing wrong? 

Note, I know it's not the same as getting fresh fish but I wonder is there an extra cleansing step I missed? Does mold survive the cooking process to rain in taste?
Basa is in the catfish family (http://en.wikipedia.org/wiki/Basa_fish), so it shouldn't require any special treatment.

Buying frozen fish, even from different stores, you may be getting it from the same supplier.  Perhaps it's something the supplier is doing, some kind of preservative treatment or something of that nature that your husband can taste, but you can't.  Check the ingredient label on one brand that you've purchased before and look for what was used, if anything, to treat the fish.  Then, assuming something was used, seek out a different brand and check its label to see if they used something different.

Now, all that being said, I've purchased Basa from the seafood counter before.  Coming from Vietnam, it had to have been previously frozen, but it had no real scent at all.  After you defrost the fish, it should have very little scent.  A strong "fishy" odor just means you have old fish, and perhaps he's picking up on some funky compounds in the old fish (some people are much more sensitive to bitter flavors than others).