As a long-time user and promoter of Purina products, I find this to be a very fascinating thread.
My experience is as follows:
Years ago, I needed a feed to support a huge population of hybrid striped bass. I began to purchase bags of Aquamax. The product was consistent and reliable. It wasn't hard to order, and my fish grew relatively rapidly on it.
After a period of time in which I introduced Aquamax diet to several different species, including bluegill, hybrid striped bass, redear sunfish and channel catfish, I began to suspect that there were some systemic stressors in the food. After fileting some of the bluegill that had been raised on Aquamax, I noticed white colored livers, and a lot of tissue in the abdominal cavity that was different than I was used to. I also found that fish that ate Aquamax grew well and survived well as long as there were other components to their diet, such as fish or invertebrates. But the fish that were subsisting entirely on Aquamax appeared to "top off" at a certain size. After lengthy discussions with experts in the field, there was a general conclusion that part of the process to create the feed may be limiting the fish's ability to live long lives. I never saw ANY scientific data to support or refute these concepts. All evidence was anecdotal, but seemingly consistent between all experts that I talked to.
A couple of years ago, I became a little disenfranchised by the fact that Purina was using my image, and some videos to promote their product, but were very content that I was paying more for their product than anybody else I knew. Apparently there is some type of tear in the fabric of the universe that makes feed more expensive in Lincoln, Nebraska than anywhere else in the world. I am not a person who lives by entitlement, but I still thought maybe there could be some sort of process that would allow me to get fish food for the same price as everybody else, instead of more....but that's another story.
This spring I had some difficulty acquiring my Purina Aquamax, and when I did finally receive it, it looked entirely different. It smelled different, it floated different, and it left no slick on the water. Instead of the inside of the bag smelling like fish, it smelled like burnt toast.
About that time I was contacted by Matt Rayl to try some new feed that he was helping to formulate. I took two identical cages of age-1 redear sunfish, and have been feeding one cage the Purina Aquamax, and the other cage has been getting the Optimal.
I am still in the process of assessing the relative growth rates. I realize there are many factors that affect growth rates--both short and long term--but I will say that after about 10 weeks, the palatability of the Optimal appears extremely good and the growth rates are currently significantly higher with the Optimal. I'm hoping to eventually sacrifice some of these fish to test the livers and other internal organs for signs of disease.
Again, I hope everybody realizes the definition of the term ANECDOTAL...but currently the Optimal feed seems to deliver significantly higher growth rates, better coloration, and more aggressive feedings. Obviously there is no way at ten weeks to really tell what the long term ramifications are. Let's just say I'm VERY OPTIMISTIC that there is a strong new player in the field. Perhaps the folks at Purina can tell us why the new feed smells like burnt toast instead of oily ocean fish. I've even noticed that when you broadcast the new Aquamax that there is no surface slick like I've been seeing for years.
To be perfectly honest, I don't really care who has the best product...I just want to be feeding it to my fish. Life goes by way to fast to not feed the best product. Let's hope that ultimately both products thrive and continue to try to produce the best and healthiest possible fish feed.
Holding a redear sunfish is like running with scissors.
