Fishkeeping Tips 7: Heaters and Lights


    Not all aquariums require a heater. Let the temperature requirements of the fish you keep, and the temperature of
    the room the aquarium is in determine whether you wish to purchase a heater. You may find that even with
    some fully tropical fish you may not need the heater to stay plugged in over the summer. Keep a thermometer in
    the tank. A heater malfunction can wipe out a tank of fish, so use a good heater when you need to. ALWAYS read
    up on any fish you keep to determine their temperature needs. As a rule, loaches, goldfish, Goodeids, some barbs, 
    most minnows (danios, rasboras, white cloud mountains, etc.) will do well from 68 to 75 degrees, and do not require
    a heater, certainly during the summer. Most all Cichlids and many other species do require a heater to keep the
    temperature at 75 degrees or above. Again, there are exceptions, so read up on every fish you keep.
    Be careful that a tank is not in a room that will heat the water past 85-90 degrees. The swords sold  here
    are kept at 72-77 degrees.

    Don't pinch pennies with the heater. Get a decent heater at 2.0-2.5 watts per gallon. A 10 gallon tank requires
    a 25 watt heater, a 100 gallon can get by with a 200 watt heater. I prefer submersible heaters. I have noticed
    recently that some manufacturers, on the initial sales packaging, recommend that a much higher wattage should
    be used. Putting a 50 watt heater on a 10 gallon tank is asking for trouble, as a heater of that size will quickly
    cook your fish if it malfunctions. Also do not assume that a heater will work properly, even when initially removed
    from its packaging. Unfortunately, the aquarium heater is often the weakest link in your setup to keep the fish
    healthy. I know cichlid breeders with tanks full of $100 fish, and they will simply toss all of their heaters and
    replace them on a yearly basis, as a $30 heater can wipe out thousands of dollars of fish!

    Make sure the heater is easy to adjust. DO NOT use the temps on the dial as a guide. Use a separate
    thermometer to determine the temperature. Before plugging a heater in, let the heater bulb sit in the tank's water
    for 10-15 minutes. Turn down dial, then plug in and bring the dial up until the little heater light comes on, then check
    your thermometer against the dial. This will give you a read of the heater dial's accuracy. Then turn the dial up
    slowly in quarter turns if you wish to bring the temp. up- waiting 30 minutes to an hour between turns- until the heater
    stabilizes and turns off, gradually bringing the water up to the desired temp. When you are at the temperature you
    desire, the heater will then keep it there.

  - Fry often do better in warmer water (78-80 degrees), which will cause them to grow faster, getting past their
    initial early growth more quickly. Bring temp. down to correct level for the species as they mature.

  - When a heater malfunctions (sticks so that it stays on or sticks so that it doesn't come on), you must toss it.
    It is not advised to attempt to fix a malfunctioning heater. Those keeping and breeding fish that require higher
    temperatures with a lot of tanks will often keep the fishroom at that higher temperature, avoiding heaters
    entirely, or they will actually remove all heaters and replace them yearly to avoid disasters. A costly expense!

    Unfortunately, heaters are often an issue in a tank's overall consistency of care, and malfunctions
    that result in the loss of fish is not uncommon. Some fishkeepers have found a different way to approach
    this problem that may be common practice in years to come. Rather than allowing a heater to function until
    a problem presents itself, one fishroom has developed a monitoring system that notifies him by alert
    on his cell phone when any particular tank strays above or below the temperature parameters he has

    Simply, digital probes in each tank send signals to a computer program compiling the temperature of each
    tank every 5 minutes. A self-written computer program maintains a log of the readings for every tank-
    in this case there are about 30 tanks- that can be accessed at any time from his cell phone, and can
    be brought up on a screen at home in a graph format, with each tank represented individually, or the
    entire room compared. Analysis of each heater's performance, various brands, etc. can all be done easily.
    When there is a malfunction, he is notified within the first degree of aberration, and can address it or call
    home to possibly have someone unplug the heater until he arrives (if it is overheating). When this was last
    discussed, he mentioned that there may be home security programs that can be manipulated for this
    purpose, such as those with temperature probes to monitor for fires, etc. If anyone is able to do this for
    their fishroom, I would like to hear about it! ( )


    This information pertains only to freshwater aquariums, as algea control and light, like many aspects of keeping
    salt water tanks, can be very different.

    Premade light hoods that come with tank kits are fine. With multiple tanks many go to 4' shop light type fixtures,
    40 watt bulbs, or with CFLs (Compact flourescents) built into measured and cut plastic gutters from the hardware
    store that create a clean, professional light hood. Be careful that your light does not warm the water or cause
    overabundant algea growth. (Live plants will compete with algea for nutrients and light, holding down algea
    growth) Besides allowing us to see the fish, and create the potential for abundant plant growth, light also
    supports bacterial growth and substantially contributes to a healthy aquarium. With some species such as
    most sucker catfish, the Tiger limias, some Goodeids and Neocaridina shrimp offered at this site, algea is
    desired. For some egg layer fry, abundant algea growth may also provide a resource of infusoria, which are
    essential to their growth. Be aware that algea growth can be the result of a number of algea species, and not
    all are eaten by fish, shrimp or snails that may eat other types. Occasionally the only remedy, for some types
    of blue-green or red algea, is to thoroughly clean the tank, and then reduce your light cycle and/or reduce the
    amount of food going into the aquarium to keep it under control.

    Recent improvements in LED technology have introduced LED fixtures to the hobby. However, they are still out
    of the reach economically for even a moderate sized fishroom, and are as yet too new to the hobby to determine
    whether LED setups will survive for the long haul in a humid fishroom, with the LED lights themselves lasting as
    long as advertised. I expect they will come down in price, the units will improve, and LED lighting will one day be
    the light of choice.

                                                                       Algea Control

    Algea blooms or outbreaks are not a normal situation. A fairly clean tank with an appropriate amount of food
    being fed, moderate light 10-12 hours a day, some healthy live plants, water changes and an appropriate number
    of fish should not encounter algea problems of any routine nature. Some algea is normal for any aquarium.
    Seasonal temperature and light variations, combined with fluctuations in the amount of organic material going into
    the aquarium water can trigger occasional algea issues, all of which are problems that routine maintenance and
    observation will generally prevent. Fortunately, the occasional bout of green water and other common algea
    problems can be remedied (see below).

    Old style incandescent bulbs, (Such as a 25 watt bulb on a 10 gallon tank) can warm the water and contribute to
    algea growth if the conditions are right. Today, flourescent  shop lights and CFLs are just as good for plants, less
    expensive to operate, and last longer, without also warming the water. Using live plants helps maintain consistent,
    positive water quality while generally holding down algea growth, as they will compete with algea for nutrients.
    We all need to wipe down the insides of the glass occasionally, however, as nothing living in the tank is all that
    concerned that we see them as well as we'd like!

    Always provide sucker and algea eating fish with vegetable foods (spirulina crisps, blanched zucchini, etc.) as
    there is rarely enough algea in any aquarium to keep them going on that alone. Many plecos starve or stay
    unhealthy and undersized from the assumption that they will eat algea, and that alone will keep them going.
    It won't. The standard inexpensive plecos sold at most pet stores will get 8 inches to a foot in a year or two,
    and I have had a number of them that got that large when fed properly. Unfortunately, they are rarely seen
    larger than 5 or 6 inches, if they even live that long. No tank produces enough algea alone to keep a sucker
    catfish nourished. Once introduced, snails are nearly impossible to remove, but they too do a fair job of
    eating many, but not all types of algea. The Neocaridina shrimp also do a good job of holding down algea
    growth by eating it and the excess food that through its decomposition contributes to algea growth.

    Certain types of algea that are fairly common can be difficult to control. Blue Green algea will occasionally settle
    into a tank, identified by its darker, bluer color and strong sweet smell. It is actually not an algea, but a type of
    bacteria. Anti-bacterials can be used that are effective, but are also very expensive. Reducing the light to a tank
    and physically cleaning it out by hand have been the solutions chosen here. Certain "Hair" algeas can also prove
    difficult, as many fish will not eat them. Keeping the goodeid Ameca splendens and some gouramis can help
    algea problems not solved by other fish, but generally the light will need to be adjusted and the problem
    physically removed from the tank. Be careful, particularly with the blue/green algea not to spread it to other
    tanks on nets, etc. and keep it confined when it does occur. 

                                                                      Green Water

    A bout of green water happens when the tank water literally turns green, and you sometimes cannot even see
    the fish. This does not harm the fish. When this happens, first turn off the light. If you have more than one
    tank, do not use nets etc. between tanks that can spread the suspended algea to other tanks. Evaluate why
    the tank may have been getting too much light- is it near a window? Then consider what other factors may
    have contributed to the sudden algea growth- is there a buildup of organic waste in the tank? Had you recently
    put plant fertilizer in the tank? (Most fertilizers are formulated specifically not to encourage algea, but if the
    amount exceeded what was appropriate, algea may still take hold.) Did you recently add water that may have
    brought the water-borne algea with it, or not changed any of the water in too long?


    When faced with a period of green water or algea growth that has gotten out of control, and past where simple
    scrubbing with a green "scrubby" won't solve the problem, first do a large water change (50 - 75%), and leave the
    light off for a week or so, keeping the tank as dark as possible while continuing regular water changes.
    (This will sometimes work). A quicker solution is to use one of a number of algeacide additives available from
    fish stores that will kill off the algea causing the problem. Then fix whatever it was that may have caused it to
    happen. With tanks where algea growth seems excessive, the addition of a sucker catfish will usually
    solve the problem. Be sure to supplement their diet with blanched zucchini. However, a pleco will have no effect
    on green water- only the types of algea it can sctrape from the glass. Recent improvements in chemical solutions
    available at the local pet store have made removal of algea fairly quick, inexpensive and easy.

    If you want green water as food for Daphnia or certain smaller egg layer fry (such as some of the rainbowfishes),
    then simply put a container of older aquarium water outdoors when it is warm and sunny, with a small amount of
    fishfood, and give it a few days. Eventually it will green up.

                                          Providing the Right Amount of Light

    Keep in mind that the amount of light can be very important to some fish, and may determine whether you see
    them, or they choose to stay hidden in the plants. The Puntius padamya does not like strong light, and their
    color will wash out if they are not able to hide when the light is bright. But with moderate to low light and
    plants nearby to zip into, their color will stay at its best. The X. mayae and High Fin mayae, are simply shy fish, 
    and bright light in a new environment guarantees they will stay hidden in the plants until they feel comfortable
    for at least the first 2-3 days. They will then stay out in the light, but will disappear if they feel threatened.
    Low light will bring them out and provide for a far less stressful acclimation and existence. In contrast, the
    X. nezahualcoyotl, another swordtail like the X. mayae, doesn't seem to notice the light, however bright it is.

    When stressed, some of these fish will stay hidden in the plants rather than to venture out into the light even
    to feed, which may quickly cause their demise. Even when out in the open, stressed fish don't eat or breed
    as well, and may live far shorter lives. I keep the regular X. mayae in 40 gallon long bare bottom tanks with
    plants placed against the back lower half of the tank (mostly java fern) under a 4' light hood with a single
    CW bulb. The Odessas  (The P. padamya) are in 50 gallon tanks with 2 ft. broad bolbitis ferns and
    java fern, with one 60 watt CFL bulb per tank.

    The type of flourescent bulbs can be important depending on the function they serve. I use Cool White (CW) 
    bulbs in my 4' shop light hoods. They seem best for plants, though I know fishkeepers that swear by one CW
    and one WW (Warm White) bulb in each fixture to provide a broader spectrum. Your pace of plant and
    unwanted algea growth will determine which you prefer, given your water, feeding and fertilizing schedule.
    Specifically made Aquarium / Plant bulbs are probably the best, but I buy bulbs by the case, and as a rule 
    the cost of the specialty bulbs is prohibitive. I truly believe my plants could not do any better.10-14 hours a 
    day of light is appropriate, and on fry tanks (where I wish to encourage fast growth) or tanks with weak 
    plants I will sometimes leave the light on 24/7.


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