2009年3月23日 星期一
Seven steps to a successful planted tank by JBL
Aqua Journal Notes 7 -- Problems of the Initial Setup Period
Some people call the initial setup period of a planted aquarium as the terrible first week, or the terrible first month. The initial setup period is the most time-consuming and also the critical time for establishing and maintaining Nature Aquarium aquascape. Let us examine the conditions of an aquarium in this period and how to maintain the aquarium.
The dirt in the water is nutrients
Let us assume that we have set up a new planted aquarium and will maintain it for a long time. While brand new water is used at the beginning, the water right after the setup is the “dirtiest” in most cases. The "dirty" water here means that the water contains excessive nutrients, but not that any harmful substances are dissolved in the water that will affect tank organisms. Let’s think about where such nutrients are generated. In Nature Aquarium, the substrate is built at the bottom of an aquarium first. It is not simply the place where aquatic plants spread their roots, but it is a place where the nutrients that are taken up by the roots are stored ahead of time. It will become the habitat for the microorganisms that decompose the nutrients and make them available to aquatic plants. Power Sand contains such nutrients, which tend to dissolve in the water when the water is added to an aquarium during the initial set-up. Since Aqua Soil is laid on top of the Power Sand, a large amount of nutrients does not continue to leach out. The dissolved nutrients in the initial setup period must be removed through water changes. Another large source of nutrients is the dead leaves of aquatic plants. Newly planted aquatic plants often have emersed grown leaves which soon die under water. When dead leaves melt, a considerable amount of nutrients are released. For example, in a fish only aquarium, new water is circulated with a filter and fish are placed in the aquarium after microorganisms have multiplied in the filter sufficiently. However, the microorganisms need nutrients to reproduce. To encourage them to reproduce, sturdy plants, such as Amazon Sword, that are sold with emersed grown leaves are sometimes thrown into the aquarium. The microorganisms start multiplying with adequate nutrients that are leached out from the leaves and this matures the water quickly. The amount of nutrients that are released as leaves die is high enough for that to take place. Similarly, when aquatic plants are planted, they are cut to certain lengths or their roots are trimmed, resulting in a large amount of damaged cells. Nutrients leach out from such damaged areas as well. Due to these reasons, the amount of nutrients that leach out of aquatic plants in the initial setup period is unexpectedly high, thus creating the need for water changes. Nutrients leach into the water in the initial setup period the most abundantly. Frequent water changes would be the easiest method to get over the so-called terrible first week or first month.
The decomposition and absorption of the excessive nutrients
Let us consider what happens to the nutrients when some time passes after the initial setup of the aquarium. First, organic substances are decomposed in the filter. The nutrients in uneaten food and dead leaves turn into ammonia, which is converted to nitrite and then to nitrate by the microorganisms in the filter. When this mechanism is working well, the water quality stabilizes and fish can be kept without a problem. However, during the initial setup period when the filter is not functioning adequately, the filter cannot keep up with the large amount of nutrients generated in the aquarium. The nutrients exist in the form of toxic ammonia and nitrite in the water. Therefore, it is dangerous to put fish in the aquarium at this point. Due to this reason, fish are placed in the aquarium one month after the initial setup. It is advisable to test for ammonia and nitrite with reagents before adding fish to the aquarium. I call them nutrients because they are nutritional substances to aquatic plants. In fact, they are taken up and used by aquatic plants. When aquatic plants photosynthesize, they produce materials to build their bodies using nitrogen, phosphorus, potassium, and various other elements. Since aquatic plants can absorb these nutrients in the water from their leaves as well, well-growing aquatic plants absorb more. Actually, in an aquarium with high light and a sufficient CO2 injection, the nutrients in the water are absorbed by aquatic plants and the water becomes cleaner. This process is the purification of water by aquatic plants. However, the volume of aquatic plants is small in the initial setup period. The purification capacity is low until new shoots develop and the amount of photosynthesis increases. Therefore, a large amount of nutrients exist in the water. The excess nutrients that are not used by aquatic plants are used by algae, and algae proliferate in the aquarium. Since the water purifying abilities of the filter and aquatic plants are still weak in the initial setup period, it is necessary to remove excess nutrients through frequent water changes. The excess can be adsorbed by using activated carbon, such as NA Carbon, as the filter media.
The cloudiness of the water – Aqua Soil
The clarity of the water is often low and the water seems somewhat cloudy in the initial setup period. There are many reasons for this and the countermeasure depends on the reason. When the water appears whitish, very fine particles are often floating in the water. These particles may be the fine particles of Aqua Soil. Aqua Soil is made by heat treating natural soil and processing it into granules. Although they are not easily crumbled in water, the fine particles on the granules become suspended in the water when the water is added to the aquarium initially. The fine particles will not continue to come out for long. If the water becomes cloudy, the water should be replaced with new water. The cloudiness will disappear after a few water changes. The use of Clear Dash is also effective for eliminating cloudiness. Aqua Soil Amazonia is very popular among the Aqua Soil Series substrate materials due to its ability to grow aquatic plants. However, it can stain the water yellow in the initial setup period. This color seems to be caused by humic acid, which is the active ingredient of the raw material of Aqua Soil, black dirt. Since humic acid encourages the growth of aquatic plants, growing plants is easier with Aqua Soil. Still, a lot of it can leach into the water depending on the water condition. Staining seems to occur more often when the water is alkaline. However, it is a natural ingredient and does not affect aquatic plants and fish adversely. The yellow color usually disappears gradually through normal water changes. If it is annoying, it can be removed by frequent, larger-than-usual water changes or through the use of activated carbon.
The cloudiness of the water – Other causes
Regardless of the age of the aquarium, the cloudiness can become much worse in a short period of time despite repeated water changes. The water becomes cloudy as if milk were poured into it, and left untreated, it gradually turns green. This occurs when the microorganisms in the filter are not functioning sufficiently. If organic materials are not broken down by the filter and a large amount of them exist in the water, the microorganisms that feed on them multiply and cloud up the water. They become so prolific that water changes cannot keep up with them, and the cloudiness persists. The aquarium sometimes recovers if it is aerated with light, the CO2 is turned off, and if a few water changes are made over three days or so. If the condition is severe, an UV sterilizer can eradicate the microorganisms. This method removes the cloudiness in a short time.
Starting plants
If aquatic plants are growing densely and photosynthesizing actively, the water condition improves due to the water purifying ability of the aquatic plants. However, some aquatic plants grow slowly and absorb nutrients slowly as well. If the water purifying ability of the aquatic plants is highly desirable, stem plants should be used for a layout. Since stem plants establish themselves quickly and their volume increases in a short time, they absorb the excess nutrients in the initial setup period. We call this type of plants starting plants. Although stem plants are sometimes difficult to maintain in a good condition for a long time, they are great starting plants. Floating plants can also be used as long as they don’t interfere with a layout since they absorb nutrients well.
Other problems
We often hear about driftwood floating up once water was added to the aquarium after driftwood had been arranged and aquatic plants were planted. Some driftwood can float if dry. If the driftwood gets soaked in water ahead of time, it will not float easily. If it still floats, a rock should be placed on top of it to weigh it down. The rock can be removed in a week or so since the driftwood will be waterlogged and sink. The leaves of Cryptocoryne may melt right after planting. However, their rhizomes are usually intact and develop new leaves. This is a biological mechanism that allows them to cope with a change in a condition such as water quality and light source. In this respect, Cryptocoryne is a tough plant. Although it would be a problem if its leaves melted right before taking photographs for a contest, it should not be a problem if this occurs in the initial setup period since healthy leaves will develop eventually. However, melting leaves should be siphoned out with a hose since they dirty up the water.
There are other setup-time specific problems such as shrimp getting sluggish or even dying due to the insecticide that had been applied on Cryptocoryne and Anubias. However, if you are resolved to care for an aquarium meticulously during its initial setup period, it would be a lot easier to maintain it afterward.
2009年2月24日 星期二
師生家長盡心協力 譜寫「鮮魚行傳奇」
【明報專訊】大角嘴鮮魚行學校一些片 片斷斷，經常見諸報章，最新一樁是該校推行的交齊功課換食物計劃，改造了一名本來「例必欠交功課」的學生，使他變得準時交功課。這個片斷，再一次說明鮮魚 行學校校方在熱心社會人士協助下，悉心教導學生，引導學生向善，取得成績。此事使得「鮮魚行學校傳奇」，增添感人故事。
窮學生轉性奮鬥為家人加Å
有子如此父母誰不感動？
故 事主人翁是一名小二學生，入讀小一以來例必欠交功課，校方去年底推行交齊功課換食物計劃後，這名學生「突變」，準時交功課，每周換取食物回家，包括臘腸、 午餐肉、白米等。原來這名學生家境清貧，一家五口，靠父親經營「收買佬」生意為生，在金融海嘯後，生意收入跌至每月約1萬元，扣除舖租及屋租後，餘下約 2000元就是全家的生活費，遲交租、遲交電費更是司空見慣。金融海嘯前廢鐵售價每斤2元，上周急跌至每斤1角，收入大跌，生計開支更是捉襟見肘，每日只 有20元買菜，以現時物價之貴，多數只能買些廉價魚、菜頭菜尾佐餐，該名學生憑覑交齊功課，換取食物，為家人加餸。
這名學生的轉變，可能有 人認為與物質鼓勵有關，不足為法。教育理論當然不能忽視，但是鮮魚行學校這個做法，使得一名小二學生為了改善家中「伙食」而奮鬥，對於這名小孩子，是何等 深刻的洗禮和頓悟，對於這名小孩子的父母和家人，是何等安慰。相信天下間的父母得此「生性」兒子，都會感到驕傲。古時以「書中自有黃金屋」來激勵讀書人， 鮮魚行學校這一幕，卻是「書中自有午餐肉」。對於這一家人，這樣得來的午餐肉，吃來更甘香可口。相信不少教育工作者都想教出這樣的學生，鮮魚行學校做到 了。
鮮魚行學校近年聲名大噪，主要得力於校長梁紀昌所率領的教師團隊。這所學校，在梁紀昌於2002年辭去教署工作、入主當校長之前，校舍 破爛，教師怠惰，學生散漫，校內情之壞可謂臭名遠播。梁紀昌主持校務之後，大刀闊斧改革，請來一批志同道合的教師打拼，縱使2004和07年兩度面臨 「殺校」，都在師生、家長協力下，渡過難關，到去年度小一、小二收生都達標，重新獲得政府資助。
去年底，中英劇團根據鮮魚行學校的蛻變歷程，編了一齣話劇《冰鮮校園》，公開上演，鮮魚行學校教師團隊搞革命，死抗爭，努力讓貧窮子弟讀書成材的一顆真心，自此更得到傳揚和肯定。
校窮志不窮
校長老師為學生當孺子牛
鮮魚行學校的巨大變化，總結起來，應該有如下幾點。
(1)校長與他所率領教師團隊的盡心盡力。該校學生大多家境清貧(有42%學生來自綜援家庭或領取金額書簿津貼)，家長為口奔馳，無暇照顧子女學習，據知校長和老師逐一登門造訪家長，以了解學生的處境，使學校與家長之間建立起良好互動，取得家 長信任，有利於對學生因材施教。加上採取開放校園等措施，校長教師與學生之間打成一片，據知，小息時，許多時候學生會湧進校長室，與校長攬頭攬頸，校長甚 至讓學生坐校長椅，說是要讓學生體會一下將來做校長的感覺。校園這種氛圍，學生渴望上課，學習事半功倍，自然不在話下。
(2)梁紀昌校長不 以「窮學校、窮學生」為恥，開誠布公反而贏得支持取得大量資源。鮮魚行校內被形容為一個「二手市場」，大至教師桌子，小至花園藤椅，都是熱心人送贈。現在 校內桌椅大小不一，有的木製，有的是L形，有的大得可以睡覺。這種不規則，對於學生可能是最佳教材，讓學生切身體驗珍惜、節儉之美德。香港社會相對富裕， 許多時候人們棄用的物品，其實仍然簇新可用，鮮魚行擺出一副「窮樣」，得以廣納大批剩餘物資，做法聰明可取。
(3)教師對學生的照顧，除了 學業，還有生活。例如少數同學獲校方安排，每隔兩星期便把學校收集得來的廢紙，送到附近的回收商變賣。所得金錢雖然不多，特別是金融海嘯之後，廢紙價格大 跌，學校仍然盡量幫助清貧學生。另外，還有回收舊校服、書包或學期末以每本1元回收校簿等，諸如此類做法，除了金錢以外，最重要是使同學們領略環保信息， 這種言傳身教，學生在潛移默化中，對其人格塑造和建立積極的人生觀，會有莫大得益。
(4)許多人都認為香港人冷漠，但是鮮魚行變革過程中， 個別社會人士所顯露熱情，為「鮮魚行傳奇」提供了一定物質條件。例如交齊功課換食物計劃，就是有熱心人接連捐贈各種食物所致，這些有心人去年聖誕節，還給 該校師生每人送贈一盒臘腸及鴨遤腸，其心細如塵，使人感動。又例如該校上一學年，獲熱心人捐出1萬元，讓20名學生得以參加劍橋英語試，其中6人得到滿 分，全部報考學生在口試都獲滿分，成績之佳，使人刮目相看。還有是去年3、4月間流感肆虐之時，有新潮涼茶舖給學校送去300多盒包括雞骨草、夏枯草、花 旗參蜜等飲料，供師生抗擊流感。
這些情，顯示鮮魚行學校師生的努力和成績，已經得到社會認同，其他學校可能認為若得到捐助，「我也會做喇」。問題不在這裏，問題在於鮮魚行學校為何能夠打動人心？
英基申請6億元建兩校舍
窮措大鮮魚行誰更富有？
鮮 魚行學校從其學生背景到校內景，在在顯示一個「窮」字，但是鮮魚行學校師生之「富有」，卻使得許多教育工作者欽羨。近日，英基學校向當局申請約6億元用 以興建兩所校舍，日後英基這校舍外觀之美輪美奐和學生家境之優越，鮮魚行學校、學生當然望塵莫及，但是「鮮魚行傳奇」所演繹的富有內涵，誰又可以說英基學 校較鮮魚行學校「富有」？
鮮魚行學校的成功，其實寫出一條道理，就是：成功的學校，不一定由金錢堆出來，只要教育工作者全心全意、全力以赴，雖然缺錢，也一樣可以取得使人矚目的成就。
2009年2月12日 星期四
Nature Aquarium Fertilization
Nature Aquarium Fertilization
There are various products available for adding nutrients to a planted tank, but adding nutrients can affect the condition of aquatic plants and an aquarium adversely unless a truly necessary nutrient is added when it is needed. This article discusses how to select and use a suitable fertilizer depending on the condition of an aquarium.
Necessary nutrients for aquatic plants
Aquatic plants absorb necessary nutrients through the surfaces of their leaves and from their roots. The three major nutrients that plants need in large amounts are nitrogen, phosphate and potassium. In an aquarium, nitrogen and phosphate are supplied rather excessively from fish waste, uneaten food, and dead leaves, and therefore it is often not necessary to add them. On the other hand, potassium tends to run short and therefore needs to be replenished. There are other nutrients that aquatic plants need. Although iron and other trace elements are required in small amounts, deficiencies of these cause plants to grow poorly. Leaves may bleach or turn yellow, or the plants become stunted and weak.
Removing excessive nutrients
Excessive nutrients, such as nitrogen and phosphate, are not completely absorbed by aquatic plants and remain in water. Various algae use them and proliferate in the aquarium. The excess nutrients need to be removed to prevent algae from developing. The easiest way to accomplish this is to do water changes. Adding necessary nutrients after removing excess nutrients is the key to proper fertilization of a planted aquarium.
Potassium shortage
Potassium has important functions in the body of a plant such as facilitating protein synthesis. Deficiency of it causes photosynthesis to become sluggish, and leaves may bleach. Although potassium is an extremely important nutrient for maintaining a planted aquarium, it tends to run short since its supply in an aquarium is very limited. Therefore potassium needs to be added continually. Brighty K allows us to add potassium easily. Adding a proper amount daily enables us to grow healthy aquatic plants over a long time. Since Brighty K also neutralizes chlorine in tap water, it is great for water changes in a planted aquarium.
Adding nutrients based on the condition of an aquarium
The condition of an aquarium varies from aquarium to aquarium. The amount of nutrients to be added depends on the condition of an aquarium. Let us examine how it should be determined.
Selecting a regimen by aquarium stage
Let us examine the condition in three steps based on the amount of time passed since the initial set up of an aquarium.
1. A newly set up aquarium
Plants that are purchased for a newly set-up planted aquarium are often emersed grown plants, and they tend to lose lower leaves. Even if they have submersed grown leaves, their lower leaves may melt due to a change in the water quality. This causes the nitrogen content of the water to rise considerably. If its filter is also newly set up, the condition of microorganisms in the filter is not adequate yet to purify the water, and therefore the water quality is not stable. Newly planted aquatic plants do not start growing and absorbing nutrients right away. All these factors create a condition in which algae develop easily. It is necessary to remove excessive nitrogen through water changes to resolve this situation. Diligent water changes supplement the lack of filtering capacity. It is important to encourage plant growth and let the plants take up nutrients in order to create the condition under which algae cannot grow well. Green Brighty STEP1 is a liquid fertilizer suitable for this period. It is a well balanced mix of various trace elements required for the development of new shoots and roots. It encourages the development of healthy new shoots. It can be added without fear of inducing algae since it does not contain nitrogen, phosphate, or potassium.
2. An aquarium with vigorously growing aquatic plants
If an aquarium is maintained well after setting it up, the water quality stabilizes in one to three months, and aquatic plants will grow densely. In such an aquarium, aquatic plants grow fast and run out of trace elements resulting in bleaching of leaves. Therefore one must be careful to replenish these trace elements. Green Brighty STEP2 is a fertilizer intended for this period. It allows you to replenish trace elements easily. Since it is fortified with iron in particular in a form that is readily absorbed by aquatic plants, it is quite suitable for the aquarium where aquatic plants are growing fast, and it prevents bleaching of leaves. This product does not contain nitrogen, phosphate, or potassium either.
3. An aquarium more than one year old
In an aquarium that has been set up for a long time, the growth of aquatic plants slows due to declining conditions such as a hardening substrate. An aquarium in such a condition, which may be considered a sign of aging of a planted aquarium, can be rejuvenated by invigorating aquatic plants and enjoyed over a long time. Green Brighty STEP3 is used for such a case. It replenishes iron, various other trace elements essential for physiological responses, and potassium, and thus revitalizes aquatic plants. It does not contain nitrogen and phosphate.
Selecting by plant type
Different plants have different growth speeds, and their nutrient uptake differs depending on their growth speed as well. Their growth speed also changes with the condition of aquarium environment. Let’s look at the different ways fertilizers are used to accommodate them.
1. An aquarium with a lot of light-loving, fast-growing aquatic plants
Heliophytic plants that love a bright environment grow fast and absorb a lot of nutrients proportionately. In an aquarium planted with a lot of these plants, nitrogen and phosphate, which tend to be excessive in other aquariums, become depleted. Nitrogen and phosphate can also become deficient if the number of fish is small in comparison to the volume of aquatic plants, or when an aquarium has been set up for a long time and the nutrients in Power Sand in the substrate are depleted. Under such conditions aquatic plants cannot grow, and the symptoms of deficiency such as bleaching leaves show up. Green Brighty Special LIGHTS (for heliophytic aquatic plants) is a general fertilizer that contains nitrogen, phosphorous, potassium and various trace elements. It is suitable for an aquarium in which aquatic plants are growing densely and nutrients tend to be depleted fast.
2. An aquarium with slow-growing aquatic plants
Aquatic plants that can be grown without a very strong light, such as Anubias, ferns, and Cryptocoryne, grow gradually, and it takes time for them to become dense. The substrate tends to get old and harden from oxidation over time. This often causes root rot and hinders the growth of plants. Green Brighty Special SHADE is a general fertilizer that contains nitrogen, phosphate, and trace elements and supplies effectively the nutrients that sciophytic aquatic plants require.
3. An aquarium with aquatic plants with strong root systems
Echinodorus and Cryptocoryne are the type of plants that grow by spreading strong roots in the substrate. When setting the substrate, Power Sand is laid as a base fertilizer to supply nutrients to aquatic plants continuously. This is especially effective for aquatic plants with strong root systems. However, the nutrients become depleted over time as these aquatic plants grow steadily. The nutrients must be added before it runs out. Iron Bottom and Multi Bottom are handy for this purpose. These stick type solid fertilizers can be inserted into the substrate easily. We recommend applying them in a half to one year after setting up an aquarium.
A convenient dispenser bottle
It is not a good idea to add a week’s worth of liquid fertilizer once a week to replenish necessary nutrients to aquatic plants. It is important that a necessary nutrient always exist in the amount required without excess. If a lot of it is added at once, the excess will be used by algae. It would be ideal to add a small amount of necessary nutrients continuously. More practically, one can add daily the amount of nutrients that aquatic plants absorb in one day. The dispenser bottle of the Brighty series is handy for this task. The daily dosage in milliliters is displayed on each bottle of Brighty series fertilizer. This is only a guideline for a standard planted aquarium. The actual dosage varies depending on the volume of aquatic plants and their growth condition (See the instructions provided with each product.) The bottle dispenses approximately 1 ml each time the pump is depressed. The desired amount of fertilizer is added by simply counting the number of depressions. This enables you to add the right amount of fertilizer without excess or deficiency and prevents algae development caused by excess nutrient addition. It is important to add a fertilizer regularly every day while monitoring the condition of aquatic plants.Deep sea water
Deep sea water is very pure and rich in various minerals. Deep sea water has attracted a lot of attention in recent years and it is utilized widely by the fishery industry and various other fields. Green Brighty STEP1, STEP2, STEP3, Special LIGHT, and Special SHADE contain deep sea water that was pumped up from the Sado Strait in Niigata prefecture. It is rich in minerals and therefore very effective for growing aquatic plants.
