Rinse fillets with freshwater or saltwater or not at all?

I found that perch with a sprinkle of Tequila Lime powder pan fried quick and slapped into a sammich with some slaw is really good.

But if you had the choice of swapping out that perch fillet with a petrale sole, or a lingcod, or a rockfish, or a salmon, or a halibut, would you still stick with the perch?

I found that perch with a sprinkle of Tequila Lime powder pan fried quick and slapped into a sammich with some slaw is really good.

But if you had the choice of swapping out that perch fillet with a petrale sole, or a lingcod, or a rockfish, or a salmon, or a halibut, would you still stick with the perch?

(Sorry for the unintentional edit above - it's back to original now.)

Well of course not but I'm not always fishing where I can catch those other species.

Ok, I am learning a lot from this. Say you wanted to try the salt water freezing in ziplocks, but you failed to bring home ocean water. What ratio of kosher salt to water would you mix?

I found that perch with a sprinkle of Tequila Lime powder pan fried quick and slapped into a sammich with some slaw is really good.

Did you wait around all morning to post at exactly 5:55:55, or was that a happy accident?   

Did not plan that at all.  Didn't even notice it until you said something.   

I found that perch with a sprinkle of Tequila Lime powder pan fried quick and slapped into a sammich with some slaw is really good.

But if you had the choice of swapping out that perch fillet with a petrale sole, or a lingcod, or a rockfish, or a salmon, or a halibut, would you still stick with the perch?

Even though I like extremely fresh donuts from a really good bakery, I'll eat a cheap day old donut that was mass produced just easily. 

To me it's not really a choice of "this instead of that", it's more like a choice of "this and/or that".
Sometimes a guy targets a different fish for different reasons.  I like perch so on occasion I fish for them. 

I don't know if this would help cure mushy, but when I worked in Alaska at a freezer plant we would flash freeze the fish whole, then dip them quickly in very cold water with a little bit of corn syrup in it. This 'coating' quickly froze and provided a barrier, primarily against freezer burn, according to QC. The corn syrup is the secret and prevents the ice from cracking and flaking off.
You could try wrapping your filets in cling wrap to prevent dehydration and freeze over night, then dip and vacuum seal. Be interesting to know if this helps.

Another thing to be aware of is that it's very important you freeze your fillets as quickly as possible, i.e. 'flash freeze'. The reason why anything turns soft after being frozen is because of cellular breakdown. This happens because when water freezes slowly it forms long crystals that rupture the cell wall. However, the faster something is frozen, the less crystal grown.
I vacuum seal my fillets and lay them out single layer wherever I can in the freezer. Next morning I box them up. Ideally you would lay them out on an empty rack so air circulates all around but I usually don't have that kind of room. If you just box them up and put them in the freezer, the fillets in the center at least might take 48 hrs to freeze, causing a lot of cell damage.
From Wiki we have:
Flash freezing is used in the food industry to quickly freeze perishable food items (see frozen food). In this case, food items are subjected to temperatures well below water's melting/freezing point.[clarification needed] Thus, smaller ice crystals are formed, causing less damage to cell membranes

Again, I'm not suggesting I follow best practices, but I am suggesting that I end up with great food.

Here's lingcod fish'n'chips from the weekend. This was made with 2016 lingcod I found in the back of the freezer. I do rinse my fillets with fresh water, and I freeze them in fresh water. The fish was easily better than any restaurant fish'n'chips I've had outside of Alaska.

OMG Captain Redbeard, that looks so good, I came back to the post and it looks even better the second time.  I had to login just to give kudos.  Nicely done!

OMG Captain Redbeard, that looks so good, I came back to the post and it looks even better the second time.  I had to login just to give kudos.  Nicely done!

Thanks! All credit should really go to my wonderful wife who not only makes great food but also fillets better than me. I will pass along the nice comment to her.

Here's a good article speaking to the issue & supporting most of what's been said already.
https://www.soundingsonline.com/voices/from-the-brine-to-the-broiler-the-right-way-to-handle-fish

Here's a good article speaking to the issue & supporting most of what's been said already.
https://www.soundingsonline.com/voices/from-the-brine-to-the-broiler-the-right-way-to-handle-fish

Wow, that's a great article. This section stood out to me:

...cutting live or just-dead fish can destroy the quality of the resulting fillets. Heed the former advice about bleeding and chilling, but also be sure to let fish rest for at least an hour post-mortem before they see the knife. Some species’ fillets will literally disintegrate in the pan if you fail to let flesh rest before cutting.

This might be why some of my fish seems to turn out firmer than other folks I talk to; I usually bleed fish immediately and then they go in the cooler whole on ice when I get back to the car where they stay until I fillet them, which is often the next day.

Here's a good article speaking to the issue & supporting most of what's been said already.
https://www.soundingsonline.com/voices/from-the-brine-to-the-broiler-the-right-way-to-handle-fish

Wow, that's a great article. This section stood out to me:

...cutting live or just-dead fish can destroy the quality of the resulting fillets. Heed the former advice about bleeding and chilling, but also be sure to let fish rest for at least an hour post-mortem before they see the knife. Some species’ fillets will literally disintegrate in the pan if you fail to let flesh rest before cutting.

This might be why some of my fish seems to turn out firmer than other folks I talk to; I usually bleed fish immediately and then they go in the cooler whole on ice when I get back to the car where they stay until I fillet them, which is often the next day.

To that I would add not to filet a fish in rigor. Either do it before rigor sets or wait for it to pass. You can delay onset of rigor with ike jimi by several hours to a couple days depending on technique and fish species.

Here's a good article speaking to the issue & supporting most of what's been said already.
https://www.soundingsonline.com/voices/from-the-brine-to-the-broiler-the-right-way-to-handle-fish

Wow, that's a great article. This section stood out to me:

...cutting live or just-dead fish can destroy the quality of the resulting fillets. Heed the former advice about bleeding and chilling, but also be sure to let fish rest for at least an hour post-mortem before they see the knife. Some species’ fillets will literally disintegrate in the pan if you fail to let flesh rest before cutting.

This might be why some of my fish seems to turn out firmer than other folks I talk to; I usually bleed fish immediately and then they go in the cooler whole on ice when I get back to the car where they stay until I fillet them, which is often the next day.

To that I would add not to filet a fish in rigor. Either do it before rigor sets or wait for it to pass. You can delay onset of rigor with ike jimi by several hours to a couple days depending on technique and fish species.

Can I ask why?

Here's a good article speaking to the issue & supporting most of what's been said already.
https://www.soundingsonline.com/voices/from-the-brine-to-the-broiler-the-right-way-to-handle-fish

Wow, that's a great article. This section stood out to me:

...cutting live or just-dead fish can destroy the quality of the resulting fillets. Heed the former advice about bleeding and chilling, but also be sure to let fish rest for at least an hour post-mortem before they see the knife. Some species’ fillets will literally disintegrate in the pan if you fail to let flesh rest before cutting.

This might be why some of my fish seems to turn out firmer than other folks I talk to; I usually bleed fish immediately and then they go in the cooler whole on ice when I get back to the car where they stay until I fillet them, which is often the next day.

To that I would add not to filet a fish in rigor. Either do it before rigor sets or wait for it to pass. You can delay onset of rigor with ike jimi by several hours to a couple days depending on technique and fish species.

Can I ask why?

They are harder to filet, and easy to damage when you have to force them to straighten out. Rockfish especially will separate which causes them to fall apart when cooked. They will also firm up some if you allow rigor to pass.