Reef Tank Maintenance, Part 1
Setting up a tank and getting it to run successfully is fun and exciting. Maintaining it properly is neither fun nor exciting, but it is crucial to the long-term health and success of the tank and its inhabitants. Unfortunately, the mundane task of maintenance is an often-overlooked aspect of a successful tank. While maintaining a tank can not be made more fun, it can be made a little easier and less time consuming with proper planning. This will then lead to the one maintenance task that is always pleasurable: watching the tank.
As with everything, proper planning is essential, and keeping a proper log is not only useful, but it can help to make maintenance easier. A log does not need to be elaborate or complicated. All that is necessary is a method for keeping track of the tank's parameters, i.e. temperature, pH, salinity, etc. Other things that can be noted in a log include; when new animals are added, their approximate size, when they die and the possible reason. The general appearance of the tank and individual species should also be noted. Equipment changes should be noted such as when bulbs are changed or heaters replaced etc. This all may seem rather trivial, but by keeping a log it is often possible to head off problems before they get worse and, more importantly, determine their cause.
In my own experience, a log has proved invaluable as a diagnostic tool for determining why something bad is happening. In one instance in my show tank, which houses a large number of wrasses and Anthias, a large number of these fish (6) all jumped from the tank within a two week period. My journal revealed that 3 weeks prior to this a new wrasse had been introduced. This fish never bothered another fish when the lights were on, however once the lights went out this fish became the neighborhood bully. This fish was then removed and the unscheduled flights ceased. Granted I probably would have realized what was happening sooner or later, keeping a log gave me an indication earlier that this fish was suspect.
Once a log has been set up it should be noted how often maintenance tasks need to be done and they should then be scheduled accordingly, i.e. water changes weekly or bi-weekly, bulb changes every 6 or 9 months, etc. When tasks are regularly scheduled, they are more likely to be done. Also if something wears out sooner than expected, such as a bulb, it can be noted. When new equipment is added or changed it should also be noted on the log so that the age of all equipment can be tracked.
The most time consuming and least pleasurable task that needs to be done is a water change. There has been much debate as to whether water changes are necessary or not, as well as how often and how much should be changed. After experimenting with just about every water change scenario possible, the system that I now employ is a 5% change weekly.
I now use a method for changing water that makes the process less painful. An old aquarium that is approximately 5% of the show tank's size is used as a mixing tank. A clean garbage can or other vessel can just as easily be used. Clean new water is mixed with salt to match the salinity of the tank and allowed to sit in the holding container for at least a couple of days with an airstone or powerhead in it. The proper amount of salt needed should be weighed or measured out so that at future water changes the needed amount can be simply scooped out. A powerhead rests on the bottom to aid in mixing and to keep the water moving and well aerated. The temperature of this water is heated to match the temperature of the tank.
When it is time to do the change, water is drained into buckets to match the desired amount. Once the proper volume to be replaced has been removed, the tank can be marked with an indelible marker at this level. By doing this during future water changes the tank can be drained directly into a sink or drain so that no hauling of buckets is necessary.
To expedite the water change and to keep the time that some of the live rock or corals may be exposed to air to a minimum a powerhead can be attached to the refill line from the clean water tank or bucket. By doing this it is possible to do a 10% water change on a 400 gallon tank in as little as 10 to 15 minutes.
During a water change, as much detritus, dirt and algae as possible should be removed from the tank. A bulb baster should be used to squirt the live rock to help dislodge any detritus that has settled there and aid in its removal. This helps to keep any long-term dead spots from forming and reduces the likelihood of an algal bloom.
One thing should be noted when doing water changes that determines how beneficial the change is for the tank. That is, a water change is only beneficial when the new water is of higher quality than the water it is replacing. Since water from many water companies is less than optimum quality, many hobbyists have found it advantageous to invest in either a deionizer/reverse osmosis unit for water purification: such as those made by Kent or Spectrapure. These units act to remove harmful chemicals and metals from tapwater. In most instances, they are a useful addition necessary for the long-term health of a reef aquarium. However if algae blooms or unexplained fish deaths are a constant battle then it may be necessary to look further into the quality of the tapwater. If one of these units is purchased, maintaining it also becomes part of regular maintenance. To do this a deionizer will need to be regularly recharged and the membrane in the deionizer will need replacing. These should also be noted in the maintenance log.
Just as water changes are a necessary evil so too is the addition of trace elements. Unlike the larger elements that make up the bulk of seawater the trace elements occur at levels of one ppm or less. The addition of these elements should occur on a weekly basis. There are several good trace elements on the market, such as those manufactured by ESV, SeaChem and Korallin. The choice depends on what one feels the tank is missing or is being removed. Some lesser quality additives may cause slime algae blooms when dosed according to their directions so another recommendation would be to start at a dose lower than on the directions and gradually titrate up. In many tanks where adequate water changes are being made and the animals are well fed it may not even be necessary to use a trace element supplement. Let your tank's condition be the guide.
While many aspects of tank maintenance require adding things an even greater number require removing things. The first thing that needs to be cleaned on a regular basis is the protein skimmer. The scum collection cup should be emptied every three or four days. While this is being done the neck of the skimmer should also be wiped clean. This is not only aesthetically pleasing but it also makes the skimmer operate more efficiently. It is also necessary because the scum that collects often does not have a very pleasant odor.
After cleaning the scum cup and neck assembly, the entire skimmer should be taken apart and cleaned every six months. This is necessary in that over time sediment often begins to accumulate in the bottom of the skimmer and this can reduce the efficiency of the unit. Lastly, for maintaining adequately small bubbles and for peak efficiency the air stones should be changed in a skimmer once a month if the skimmer being used is a countercurrent model.
If a venturi driven model is chosen, the skimmer should be shut off for 5-10 minutes every week in order to allow for the venturi opening to de-clog from the salt creep that occurs. Over time in a venturi skimmer, at the air/water interface, salt creep forms that makes the venturi opening smaller. This results in the skimmer losing efficiency. By turning off the skimmer, water comes into contact with the salt and dissolves it. This reopens the venturi and allows it to operate at peak efficiency.
High quality carbon such that made by Seachem and ESV is useful for removing harmful compounds from a reef aquarium that a skimmer may miss. When carbon is first introduced, a small quantity (50 grams/40 gallons), should be introduced. This is because the carbon will not only remove harmful compounds, especially those which cause yellowing in the water but it will also remove trace elements. If too large an amount is added initially, it may allow too much light penetration and this can shock and kill some of the corals and coralline algae. Once the tank has become acclimated to having carbon in it the amount of carbon can then be increased to where the amount is eventually 100grams/40 gallons. This should be done gradually over the next two to three months. After this time, 1/3 of the carbon should be exchanged every month for fresh carbon.
A less frequent maintenance job that needs to be done is maintenance on the lighting system. Every week the lights should be checked while they are off for any salt deposits that may have occurred. While it may appear trivial, salt build up on the lights can dramatically reduce the amount of light being transmitted. While they are off, the lights should be wiped off with a wet towel and then dried thoroughly. If salt creep or calcium deposits are a problem, a combination of rubbing alcohol and white vinegar can be used to clean the bulbs and reflectors. This mixture dissolves these deposits and does not streak. Under no circumstances should the lights be cleaned while they are hot. This is important in that water hitting hot lights could cause them to crack or in the worst case explode. In addition to cleaning the lights, any surfaces below or behind the lights should be cleaned as well. Salt and dust creep on these surfaces can also lead to a diminution of light.
In addition to cleaning the bulbs, it is also necessary to change them at regular intervals. Most fluorescent tubes should be changed every 8 to 9 months. When viewing the tubes, this may appear unnecessary in that the tubes still appear to be bright. But in 8-9 months, fluorescent tubes can lose as much as 60% of their intensity. The exact time to change the bulbs depends not only on the bulb, but also on how long it is on every day. If your light cycle averages 12 hours then approximately 6-7 months of use is what you can expect from your bulbs. If the light cycle is longer, 13-14 hours, which should be the maximum, the bulbs should be changed sooner. If the light cycle is 10 hours then an 8-9 month interval between changes is good.
Another maintenance task that should be performed regularly is water testing. A longer discussion on water testing and what the parameters should be will be in the next article. Some tests only need to be performed if there appears to be a problem. These include ammonia and nitrite. Some other test should be performed on a more regular basis so that it may be possible to detect a problem and correct it before it causes any serious damage. The tests that should be done weekly include temperature, salinity, nitrate, phosphate, calcium and alkalinity.
Mike Paletta is the author of The New Marine Aquarium and Ultimate Marine Aquariums. He has been in the hobby for over 15 years and has written numerous articles for Aquarium Fish Magazine, Tropical Fish Hobbyist and Aquarium Frontiers.