162 



L. HILLIS-COLINVAUX 



Table XI. Chemical Analysis of the Commercial Abtificial Seawater 



"Instant Ocean"" 



Component 



Percentage by weight 



NaCl 



MgS04.7H,0 



MgCla.eH^O 



CaCla 



KCl 



NaHCOg 



KBr 



H3BO3 



SrC]a.6H,0 



MnS04.H20 



NaaHPO^.THaO 



LiCl 



N'a2Mo04.2H20 



NaaSgOg.SHaO 



Ca(C6Hii07)2.H20 



Al2(S04)3.18H20 



RbCl 



ZnSO^.THgO 



KI 



EDTA NaFe 



C0SO4.7H2O 



CUSO4.5H2O 



65-226 



16-307 



12-762 

 3 261 

 1-737 

 0-4963 

 007206 

 006214 

 0-04689 

 0009379 

 0-009379 

 0-002343 

 0-002343 

 0-002343 

 0001669 

 0-001202 

 00004005 

 0-0002563 

 00002403 

 00001936 

 00001335 

 00002670 



" Data from Aquarium Systems, Inc., Wickliffe, Ohio, 



while the bulbous holdfast system of sand-growers may supply their 

 own. 



When the aquaria are filled with seawater to the desired level and 

 the plants added, the level of the medium is marked on each aquarium 

 wall. Water evaporated from the system is replaced every few days by 

 topping up to the level marked with distilled or glass-distilled water. 

 This maintains a constant volume and accordingly a constant salinity. 

 If the aquaria are maintained for six months or longer, the salinity is 

 monitored. The seawater is siphoned out and replaced every six to nine 

 months. 



2. Substrates 



(a) Unconsolidated. About 2-5 cm of a calcareous material and another 

 2' 5 cm of a readily available sand are used, with, for convenience, the 

 larger-grained material providing the bottom layer. 



