Despite its outstanding size of 40m, the “Greatest Nature Aquarium” is maintained using the systems made by modifying NA Goods used for ordinary Nature Aquariums. The Nature Aquarium Notes of this issue explains the systems for large size aquarium tanks, mainly 180cm tank having a realistic size.
■ Filter system for large size tanks
Nature Aquarium mainly uses external filter for water purification. For standard 60cm and 90cm tanks, Super Jet Filter ES-600 is commonly used but its filtration capacity is insufficient for larger 120cm and 180cm tanks. Usually, the filtration capacity of filter is enhanced if the amount of filter media and water circulation rate is increased. Super Jet Filter ES-1200 designed for 120cm tanks has approximately double the canister capacity and three times the pump flow rate of those of Super Jet Filter ES-600. Likewise, Super Jet Filter ES-2400 designed for 180cm tanks has approximately four times the canister capacity and five times the pump flow rate of those of Super Jet Filter ES-600. For some of the tanks larger than 180cm, multiple ES-2400 or ES-2400/EX2 units having a higher canister capacity are installed to provide greater filtration capacity. For massive Nature Aquarium such as 7m and 4m tanks at Sumida Aquarium in Tokyo Skytree Town as well as 40m tank at Oceanário de Lisboa, an outstanding filter capacity is realized by installing intensive filtration systems using overflow system.
■ Water flow and CO2 system
In aquarium, sludge can easily build up in the parts with stagnant water and this can cause the growth of spirogyra algae and blue green algae which are hard to remove. Large aquariums with larger capacity and water volume tend to have areas with stagnant water and therefore, it is important to create adequate water flow that runs through the entire aquarium. For this purpose, it is recommended to install more than one unit of outflow pipe or provide filters on both sides of the tank to minimize the occurrence of stagnant water within the tank. Choose an appropriate approach according to your tank size. For Nature Aquarium created in a 60cm or 90cm tank, Lily Pipe Outflow is used for moderating water flow. In contrast, for 180cm or larger aquariums, there are some cases where water is intentionally pushed out of the filter at a high current to create water flow. Water flow is important in aquarium also for the purpose of supplying nutrients and CO2 to aquatic plant leaves. In particular, CO2 is hard to be dispersed through the entire aquarium without adequate water flow. The CO2 dispersion efficiency can be enhanced further in large aquarium tank by installing multiple units of Pollen Glass Beetle having a wider diffusion filter at a best location for the dispersion of CO2 bubbles by water flow. Some massive sized aquarium tanks adopt direct CO2 injection in water flow to facilitate the dissolution of CO2 in water.
■ Lighting system designed for deep aquariums
In the early days of Nature Aquarium, the NA Lamp equipped with straight-tube fluorescent lamp was used for lighting system. Later, the metal halide lamp NAMH-150W and Solar I were developed to cater for deeper large aquariums. Because light entered the water through the water surface is attenuated rapidly in water, large and deep aquariums require brighter light emitted by more powerful lamps. Grand Solar I equipped with the combination of a metal halide lamp and two NA Lamp 36W Twin emits brighter light compared with Solar I. Large aquariums displayed in Nature Aquarium Gallary and Sumida Aquarium use this Grand Solar I while massive 40m aquarium at Oceanário de Lisboa (1.5m deep) also adopted metal halide lamps. As can be seen in these cases, lighting system equipped with metal halide lamp is currently a suitable option for large aquariums.
Can CO2 Advanced System be used for large size aquariums?
CO2 Advanced System is a convenient kit that includes all the components necessary for supplying CO2 to Nature Aquarium. This set is basically designed for 60cm aqiarium and it is not suitable for large size aquarium. To upgrade a CO2 Advanced System currently in use to a system for larger aquariums, add CO2 Adapter and replace CO2 regulator (YA/Ver.2) to CO2 Attache Regulator or equivalent, and attach it to “Tower” for large aquariums. In addition, replace CO2 Bubble Counter to CO2 Beetle Counter and also replace Pollen Glass to Pollen Glass Large or Pollen Glass Beetle according to the tank size to cater to the increase in CO2 supply amount.
CO2 Glass Counter
CO2 Beetle Counter
Pollen Glass Beetle
Pollen Glass Large and Beetle have different size options for each tank size. For example, Pollen Glass Beetle 50Ø is suitable for 180cm aquarium tank.
How should I decide the amount of liquid fertilizer to be added to a large aquarium?
Basically calculate the amount of liquid fertilizer based on the volume of aquarium water. The specified amount of the Green Brighty series and Brighty K is 3ml for 60cm aquarium tank. Therefore, the amount of these liquid fertilizer to be added to a 90cm will be three times of that amount. Accordingly, the amount for 120cm and 180cm tanks will be four times and ten times of the amount for 60cm tank, respectively. Based on this calculation, 30ml of liquid fertilizer should be added to a 180cm tank and a standard 500ml bottle of fertilizer becomes empty in about two weeks. For large aquariums, it is recommended to purchase a 5,000ml bottle to refill the 500ml bottle.
Green Brighty Series
Purchase of 5,000ml bottle is an ecomonical option for large aquariums. Use it to refill the 500ml with a dispenser pump.
How should I do the water change for large aquarium?
For large aquarium tank having a large volume of water, it is not efficient to do water change using a pail as we usually do for 60cm tanks. An ideal way is to prepare a long hose and drain water directly from the tank while pouring water using another hose connected to a water tap. If you install NA Water, a water purification system, between the water tap and aquarium tank, harmful substances such as residual chlorine can be removed to ensure safe water change. To implement this method, make sure that the temperature of tap water to be added to the tank can be pre-adjusted by mixing hot or warm water. This approach of conducting draining and pouring water simultaneously using two hoses is also effective in improving water clarity of newly set up aquarium.
If NA Water is used for water change for large aquarium, removal of residual chlorine contained in tap water is made easy and there is no need to use additives such as Chlor-Off.
(From Aqua Journal #244)