David is correct. Oft marketed spirulina discs are often as high, if not higher, in crude protein than even carnivore flakes (more ash in the latter). The addition of spirulina is minimal. People, however, tend to underestimate the amount of food necessitated by limnivores such as hypostomus (h. plecostomus is exceedingly rare these days, as imports have shied away from the surinam area), which forage almost 24 hours of the day, rasping away at decaying vegetation and biofilm. Thus, for optimal growing speeds, feeding at least twice day with vegetable flakes/ spectrum vegetable pellets (whatever is suitble for tropheus, for example), with teh inclusion of vegetable shrimp mixes, frozen/live foods and carnivore pellets will boost that suck er to at least 8"by the end of a year's worth of administration.