[Walter]

Hmm,

diese Lopes Arbeit gibt´s online - aber nur gegen Bezahlung.
Hier zumindest das Abstract:
https://www.ingentaconnect.com/conte...00001/00322833

Abstract:

The objective of this study was to determine the influence of water pH (5.5, 6.0, 7.0, 8.0, and 8.5) on survival and growth of silver catfsh (Rhamdia quelen) larvae. Larvae were obtained from induced spawning in November and maintained under controlled conditions of 25 (1) °C using a water re-use system in continuously aerated 40 L polyethylene tanks (350 larvae/tank). Larvae were fed until satiation six times a day. At days 0, 7, 14, and 21 and after yolk absorption, 10 larvae from each group were randomly chosen to evaluate length, weight, and specific growth rate (SGR). Length, weight, survival, and biomass at the end of 21 days were significantly higher at pH 8.0 and 8.5. As expected, specific growth rate decreased with time. These results suggest that 8.0–8.5 is the best pH range for survival and growth of the larvae of this species.