212 AQUARIUM CONSTRUCTION 



After the considerations of size and proportions, which we have 

 already touched upon, we will now take up in order the points of 

 construction, laying particular emphasis on the factor of safety. 



Bases. The best material for general use in aquarium bases is 

 slate. It is inexpensive, durable, easily worked, free from cleavage 

 cracks, and in every way reliable. The requirements for thickness are 

 from 54-inch for sizes up to 30 gallons, to l}i inches for 130 gallons. 

 Polished Tennessee marble makes a handsome and durable base. 

 White marble is too glaring and besides is easily chipped in moving 

 an aquarium about. Also when brought into contact with aquarium 

 cement it absorbs and spreads the oil, making a bad appearance. 



Aquarium bases usually extend from one to one and one-half 

 inches beyond the frames on all sides. Slate or marble bases ought 

 to be beveled sufficiently on the upper edges and corners to take away 

 the sharpness. The necessary holes through which the frame is to 

 be clamped on can be drilled with an ordinary metal drill, but it costs 

 very little extra to have the slate-worker do this when he is finishing 

 the base. Aquaria up to 10 gallons require 4 bolts, 20 gallons 6, and 

 for the larger sizes they should be placed about 10 inches apart. 



Frame Metals. Angle brass, iron or aluminum form the best 

 metal aquarium frames. For the amateur worker, brass offers the 

 most advantages. It is easily sawed, drilled and soldered, besides 

 making a handsome appearance when polished and lacquered or 

 nickel-plated. If nickeled it should be heavily coated. Angle iron is 

 not so attractive in appearance, but is undoubtedly more rigid. It 

 cannot so well be soldered. Consequently the four corners of the 

 upper and lower frames have to be riveted through connecting elbow 

 pieces on the inside or special castings on the outside, and then the 

 whole riveted to the uprights. Aluminum has seldom been used, but 

 makes an attractive frame. As the soldering of this metal is of doubt- 

 ful durability, it is safer to rivet the same as with iron. 



For aquaria up to 25 gallons, ^-inch angle metal is suitable-; up 

 to 50 gallons, j54-inch ; up to 75 gallons, 1-inch; up to 125 gallons, 

 1^-inch. The author prefers seeing as little of the frame as possible 

 and for many years has successfully used a 60-gallon aquarium con- 

 structed with only ^^-inch angle brass, but he would not care to make 

 this as a general recommendation. It is mentioned so that if others 

 have the same idea they will know that it is a mechanical possibility. 



Unless constructed of heavy angle iron, it is best to carry a light 

 rod across short dimension of the centre of top frame of aquaria over 

 30 inches in length, to prevent bulging by water pressure. 



