CHAPTER TEN 



Marine Aquaria 



The maintenance of a marine aquarium is really much simpler than 

 is generally supposed. If aquarium lovers realized the great charm and 

 the unlimited possibilities of a marine tank, there can be no doubt many 

 more would interest themselves in this particular form of the hobby. It 

 is safe to say that not a score of persons in America at this time have 

 saltwater aquaria, although when once established they are as easily kept 

 as the freshwater kinds. Then, too, there is the fascination of collecting 

 from a field of inexhaustible variety, giving the student always something 

 new to work on, with the ever-present possibility of discovering some fact 

 of value to science or to his fellow aquarist. To those living within easy 

 journey to the shore is the added attraction of the trip to the seaside, 

 the pleasures of which are doubled by the pursuit of such a delightful 

 and absorbing study. 



Aeration. There are just a few points of radical difference between 

 the fresh and saltwater aquaria. We have elsewhere pointed out the 

 oxygenating value of aquatic plants, and shown how their work is desir- 

 able in a "balanced" or reciprocating aquarium. This factor must be left 

 out of consideration in the saltwater aquarium, for marine plants perform 

 this function to so small a degree as to become unimportant. The Ulva, 

 or sea lettuce, is the most satisfactory of the easily obtained plants. It 

 has been known to do well for quite long periods. A few bits of cork 

 placed beneath will cause it to float to the top, where it looks and does 

 best, at the same time shading the water. The beautiful Actiniae, or Sea 

 Anemones, which are flower-formed animals, present a bewildering array 

 of form and color far surpassing any freshwater plants. These were 

 once supposed to form a connecting link between the animal and vegetable 

 worlds, but this is an error, the beautiful creatures belonging purely to 

 the animal kingdom. As far as appearance is concerned, other beautiful 

 attached animals also make up for the lack of vegetable life. 



For the absence of oxygen from plants we have either to depend upon 

 mechanical processes, or to substantially reduce our number of aquarium 



