The efficacy of anaesthetic tricaine methanesulfonate (MS-222) was evaluated in four freshwater aquarium fish species, Zebrafish (Danio rerio), Guppy (Poecilia reticulata), Discu (Symphysodon discus) and Green swordtail (Xiphophorus helleri).The correct dose of anaesthetic should induce the plane 4 of anaesthesia in less than 180 s, recovery in less than 300 s and must survive when exposed during 30 min to anaesthetic. Fishes were exposed to six concentrations of anaesthetic (75, 100, 125, 150, 200 and 250 mg L À1 ) and the time of fish reaching plane 4 of anaesthesia, post exposure recovery, and the percentage of survival when fish were subject to 30 min in the anaesthetic were recorded. The optimal doses varied according to the species: D. rerio -75, 100 and 125 mg L À1 , P. reticulata -125, 150 and 200 mg L À1 , S. discus -75 and 100 mg L À1 and X. helleri -125 and 150 mg L À1 . The induction time generally decreased significantly with increasing concentration of MS-222 for all of the species evaluated. The recovery time had a tendency to increase with the increase of the MS-222 concentration for D. rerio, P. reticulata and S. discus. On the other hand, X. helleri recovery time decreased with the increase of MS-222 concentration. MS-222 proved to be effective in anaesthesia for all the freshwater ornamental species studied. The main results clearly show that the optimal dose to anesthetize is fish species dependent and it is completely wrong to extrapolate optimal anaesthetic concentrations between different species.

The aim of this study was to evaluate the influence of stocking density (0.5, 1, 2 and 3 fishL−1) and commercial marine fish diets (diet A, B, C and D) over four months on specific growth rate, condition factor, percentage without anomalous pigmentation (partial or total lack of white bands -miss-band) and survival of juvenile Amphiprion percula.Results showed that at 0.5 fishL−1 densities induced the best survival (100%) and also the maximum percentage of fish without miss-band (58.33 +/−4.417%). The maximum SGR was obtained for the 0.5 fishL−1 (0.459 ± 0.023% cm/day). However, the best condition factor (2.53 +/− 0.27) was achieved for 2 fishL−1 densities. There were no significant differences in survival (68.9 to 84.5%), fish without miss-bands (18.03 to 26.92%) and condition factor (1.92 to 2.1) among diets during the experimental period. On the other hand, diet C (with 41% crude protein) supported the best SGR (0.485 ± 0.001% cmday−1).The results suggested that stocking density are critical and more relevant when compared with the different diet tested, namely on specific growth rate, condition factor, the miss-band and survival of juvenile percula clownfish.This study has particular significance with regards to anemonefishes husbandry in terms of survival and production efficiency.

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The increasing demand for soft corals is reflected on the high attention of the scientific community during the last decades, with several studies focus on production techniques and optimization of coral husbandry. However, coral culture success is influenced by the interaction of different factors, such as water movement, temperature, nutrients, heterotrophic feeding and light conditions. Light plays a key role in the growth, reproduction and physiology of corals that host phototrophic symbionts and it has been found that the photoresponse of corals is species-specific. Several studies have already focused on the effects of irradiance on coral and its algal symbionts. Although, only a few works have investigated the role of the spectral quality of light on coral photobiology, physiology and growth. In the present study, we hypothesize that light spectrum can influence the growth performance of Leather Coral Sarcophyton spp.when exposed at identical intensities of photosynthetically active radiation (PAR). To test our hypothesis we evaluated the effect of contrasting light spectra with an identical PAR of 70 ± 10 μmol quantam −2 .s −1 emitted by T8 fluorescent lamps (used as a control treatment) and three different colours of Light Emitting Diode (LED), white, blue and red. It was evaluated survival and growth rates of Sarcophyton spp., an important soft coral in the marine aquarium trade and for the bioprospecting of marine natural compounds. Replicated coral fragments were obtained from two mother colonies and were exposed to the four types of light spectrum for a period of 30 days. At the end of the experiment period, the results showed 100% of survival in coral fragments, and specific growth rate (SGR) of 0,055 ± 0,09%/day in control group and 0,091 ± 0,019 %/day, 0,210 ± 0,031%/day and 0,380 ± 0,245%/day in, white, blue and red light, respectively. Moreover, in all treatments at end of experiment the zooxanthellae density was ±, ± and ± for white, blue and red light spectrum, respectively showing that all light promotes conditions for zooxanthellae growth. The results also showed a positive role of use a specific light spectrum in coral growth, namely blue and red spectrum. The use of light with specific light spectrum that increasing the growth and health of corals will minimizing the production costs, increasing the feasibility of ex situ production of ornamental corals and this study identify the best LED`s light spectrum for the growth of the leather coral Sarcophyton spp.