46 



Aquatic JLitt 



of my tanks bright and clean. I em- 

 ployed scrapers, pads, brushes and good- 

 ness knows what not; all more or less 

 unsatisfactory. One day I picked up a 

 piece of cuttlebone at the seashore, took 

 it home and found it to work wonders. 

 There is nothing equal to it; appears to 

 polish as well as clean the glass. Its use 

 in this connection is mentioned in one 

 of the earlier numbers of Aquatic Life, 

 but only quite incidentally. As A. L. 

 has many new subscribers now, it may 

 be well to mention the use of cuttlebone 

 in a more prominent way. No matter 

 how hard the coating, the bone removes 

 it with the greatest ease. 



(Tillaca is a genus in Crassulacaea, the 

 orpine family — stonecrops, houseleeks, 

 etc. Tillaea aquatica is an allied Ameri- 

 can species, and has been recorded from 

 some New England States, eastern Penn- 

 sylvania, Delaware and probably else- 

 where. The Australian species bears 

 some resemblance to Anacharis in general 

 aspect, but is rather brittle and seems to 

 branch more freely. — Editor.) 



Another Tank Heater 



ARTHUR KUHN 



Mr. H. M. Hale's description of an 

 aquarium heater (Aquatic Life, Sep- 

 tember, 1918) prompts me to describe an 

 arrangement which I have used during 

 two winters with success. It may appeal 

 to aquarists who do not care to use gas 

 or oil for the purpose. 



The heater consists of a narrow, cyl- 

 indrical flower-holder of glass and an 

 electric bulb of a size to be slipped into 

 the holder, with necessary wiring, socket 

 and plug. The flower-holder, which is 

 greater in depth than the water in the 

 aquarium, rests on the bottom, small lead 

 shot being used to sink it. The electric 

 bulb is placed in the holder and connec- 



tion made to the nearest electric fixture. 



Aquaria holding from eight to twelve 

 gallons have been kept sufficiently warm 

 by this scheme. The temperature may be 

 regulated by raising or lowering the lamp, 

 or by floating it in water placed in the 

 holder, the proper depth being deter- 

 mined by experiment. 



To conserve the heat, and also to pre- 

 vent fishes leaping into the heater, some 

 sort of a lid should be placed on the 

 holder. Products of combustion being 

 absent, no consideration need be given to 

 draft. 



Heating vessels of transparent glass 

 have the advantage that, even in corners 

 not receiving proper natural light, the 

 plants will grow splendidly, while the 

 fishes do not seem to be annoyed by the 

 artificial illumination. Instead of flower- 

 holders, any other vessel of suitable 

 shape and material may be used. The 

 vessel used by Mr. Hale is very similar 

 to mine, which I bought in a "10-cent 

 store." 



I prefer the old-fashioned carbon fila- 

 ment lamps, as more heat is generated 

 than by the modern tungsten bulb, even 

 though the current consumption of the 

 latter is smaller. The glare of the light 

 can be softened by grouping plants 

 about it. 



(By using an outside or waterproof 

 porcelain socket and carefully sealing it 

 with a good elastic aquarium cement 

 placed around the base of the lamp and 

 in the holes through which the wires run, 

 the lamp may be safely immersed in the 

 water of the aquarium without the pro- 

 tecting jar. — Ed.) 



Perhaps the chief concern of all organ- 

 isms is to provide material for carrying 

 on the complicated chemical processes 

 that are going on within — that is, to get 

 food and oxygen. — H. S. Jennings. 



