It has been shown in study after study that fish like BG , LMB , HSB etc in pond type environs do best when they get fish based protein/lipids (fish meal/oil)rather than other types especially plant based protein. For grazing fish like CC , tilapia , GC , GShiners the source is not so important.

I have found also that BG ect more readily eat pellets containing fish products. Plus the more you rely on pellets (aggressive feeding program) the more important this difference makes. So check the contents before you buy.

Here are a few bits of info.

However, the use of low-protein

diets has several complications. Such diets generally

contain high levels of carbohydrates, which

are often poorly utilized by fish (Wilson 1994) and

add to the quantity of undigested material entering

the culture system.



Physiologically, fish are affected

by variations in water temperature in two

ways (Hochachka and Somero 1984). First, temperature

determines the rate of chemical reactions,

and secondly, temperature dictates the point of

equilibrium between the formation and disruption

of the macromolecular structures in biological

membranes. Structural flexibility, therefore, is a

requirement for integrity of biological membranes

(Hazel 1993).

As environmental

temperatures decrease, the invariable response is

an increase in fatty acid unsaturation (Johnston and

Roots 1964; Caldwell and Vernberg 1970; Hazel

1979; Cossins and Prosser 1982). Conversely, as

ambient temperatures increase, phospholipid saturation

must also increase to avoid excess fluidity.

The dynamics of lipid composition of cells occurs

in order to maintain a constant fluid matrix for

enzymes associated with membranes (Greene and

Selivonchick 1990). Different species of fish differ

in their patterns of fat deposition and mobilization,

which in turn affects the temperature range in

which the species can grow and survive.



Diets influence the fatty acid composition in several

species of fish (Henderson and Tocher 1987;

Lovell 1989; Seo et al. 1994), and the ability of a

fish to alter its lipid composition ...is one factor that determines survival

In these fish, the fat

apparently hardens in the colder water, causing the

fat-impregnated muscles to stiffen and the fish to

become exhausted and lose movement.