Nutrition research in aquaculture historically focused strongly on impacts on fish (growth, health, etc.). With the raising importance and awareness of sustainability in aquaculture the attention in research on environmental impacts has increased. Feed is a important factor for the amount of solid and dissolved waste being discharged by aquaculture. On of the reasons of culturing fish in recirculating aquaculture systems (RAS) is its potential to reduce and control the impact on the environment. For a proper functioning of RAS solid waste manage is a key factor. Solid waste accumulation in water is the primary source for suspended solids and contributes to increased dissolved waste. Suspended solids accumulation can hamper fish health, gill functioning and hamper proper functioning of RAS (water purification units). In farms using RAS that apply proper feeding management, faeces is the major source of solid waste produced. Complete and quick removal of faeces from the water is vital in a good faecal waste management strategy being targeted at reducing the amount of none-removed faecal waste from the water. Nutrition is vital in managing faecal waste. Reduction of the amount of none-removed faecal waste can be achieved by reducing the amount of faeces egested (i.e., increasing the nutrient digestibility) and/or by increasing the removal efficiency of faeces from the water. Faecal removal efficiency (by settling and/or filtration) is an interplay between system design and the characteristic of faecal waste . Factors influencing removal efficiency are faecal pellet size, density and stability. Currently there is still a lack of knowledge on faecal pellets with many unanswered questions like: what is a natural faecal pellet and stability; are faeces characteristics different between fish species; which dietary factors determine removal efficiency; can dietary factors improve faecal stability (i.e., reducing disintegration of faecal pellets); are faecal waste characteristic determined by ingredients or nutrients within a diet; are dietary factors determining faecal removal similar between different fish species? Such knowledge is required to formulated optimal feeds for RAS. In this presentation an overview will be given on published data and in house data from studies linking dietary interventions to faecal waste management. With the major focus on factors that determine the removal efficiency as measured in various fish species, like salmon, trout, tilapia, common carp and striped catfish (Table 1). Factors that will be addressed are the impact of: feeding level; dietary ingredient composition; type of carbohydrates; type of protein rich ingredients; dietary starch level; etc.