- Location
- Port Washington NY
I was thinking of beginning to dose amino acids and was hoping to get some input. What brand are you using, how long have you been using it, do you really see a difference. Id be dosing it on my SPS dominated 40BR.
Interactions between zooplankton feeding, photosynthesis and skeletal growth in the scleractinian coral Stylophora pistillata.
Fanny Houlbr?que, Eric Tambutt?, Denis Allemand and Christine Ferrier-Pag?s
Summary
We investigated the effect of zooplankton feeding on tissue and skeletal growth of the scleractinian coral Stylophora pistillata. Microcolonies were divided into two groups: starved corals (SC), which were not fed during the experiment, and fed corals (FC), which were abundantly fed with Artemia salina nauplii and freshly collected zooplankton. Changes in tissue growth, photosynthesis and calcification rates were measured after 3 and 8 weeks of incubation. Calcification is the deposition of both an organic matrix and a calcium carbonate layer, so we measured the effect of feeding on both these parameters, using incorporation of 14C-aspartic acid and 45Ca, respectively. Aspartic acid is one of the major components of the organic matrix in scleractinian corals. For both sampling times, protein concentrations were twice as high in FC than in SC (0.73 vs 0.42 mg P–1 cm–2 skeleton) and chlorophyll c2 concentrations were 3–4 times higher in fed corals (2.1?0.3 ?g cm–2). Cell specific density (CSD), which corresponds to the number of algal cells inside a host cell, was also significantly higher in FC (1.416?0.028) than in SC (1.316?0.015). Fed corals therefore displayed a higher rate of photosynthesis per unit area (Pgmax= 570?60 nmol O2 cm–2 h–1 and Ik=403?27 ?mol photons m–2 s–1). After 8 weeks, both light and dark calcification rates were twofold greater in FC (3323?508 and 416?58 nmol Ca2+ 2 h–1 g–1 dry skeletal mass) compared to SC (1560?217 and 225?35 nmol Ca2+ 2 h–1 g–1 dry skeletal mass, respectively, under light and dark conditions). Aspartic acid incorporation rates were also significantly higher in FC (10.44?0.69 and 1.36? 0.26%RAV 2 h–1 g–1 dry skeletal mass, where RAV is total radioactivity initially present in the external medium) than in SC (6.51?0.45 and 0.44?0.02%RAV 2 h–1 g–1 dry skeletal mass under dark and light conditions, respectively). Rates of dark aspartic acid incorporation were lower than the rates measured in the light. Our results suggest that the increase in the rates of calcification in fed corals might be induced by a feeding-stimulation of organic matrix synthesis.
Extracted from:
Journal of Experimental Biology 207, 1461-1469 (2004)
Feeding has also been shown to enhance sketetal growth, suggesting that corals allocate a high proportion of the energy brought by food to calcification processes. It is important to note that calcification is also a dual process, involving the secretion of an organic matrix and the deposition of a CaCO3 fraction. The presence of an organic matrix in coral skeletons is widely documented and is considered an essential prerequisite in the formation of a biomineral structure. This matrix potentially plays key roles in various processes such as crystal nucleation and growth, crystal size and orientation and regulation of skeletal formation. Cuif et al (1999) demonstrated that the composition of the matrix was different between symbiotic and asymbiotic corals, and Allemand et al. (1998) suggested that heterotrophy is a source of aspartic acid, once of the major components of the coral matrix.
..... Allemand et al. (1998) also showed that no aspartic acid pool was present inside the coral tissue, suggesting the need for a constant supply from an exogenous source. By using 14C-aspartic acid as a precursor for organic matrix synthesis, we measured a higher incorporation of this amino acid into the organic matrix of fed corals.............
Feeding might therefore have enhanced the construction of the organic matrix by (i) supplying additional input of energy, espercially for the dark processes. Under high plankton concentrations...........uptake of organic carbon (and hence energy) may be significant and could provide some energy for calcium/proton exchange at night. Alternatively, the larger biomass of fed corals may have provided larger energy stores for dark processes. Thus, feeding might have (ii) directly provided the necessary 'external' amino acids and/or (iii) indirectly increased photosynthesis and therefore the supply of 'autotrophic' amino acids.
Yes, ReefPlus, KZ and L Carnatine. Only dose if your nutrients are low.
Like Tosiek said. Check the vodka thread on RC.
How do you know if they are low? Are there AA test kits? If not, then isn't it pretty much just guess work?
Shawn, interesting citations but again, just because something is rate-limiting does not mean that it is limiting in our artificial environments. So the question stands, is there a practical test we can do to determine if 14c-aspartic acid is deficient in our aquariums ( or any other amino-acid ) ?