Water Changes - Performing them Correctly

Routine water changes are an integral part of the overall aquarium management process.  Since all closed system aquariums develop gradually increasing levels of unwanted nutrients, successful aquarists generally employ routine water changes to dilute waste and add beneficial clean, balanced seawater, plus trace elements back into their systems.  Done correctly, a regular water change will invigorate captive reef tank inhabitants and contribute to the overall health of the aquarium, as well as reducing unwanted nuisance algae build-up.  Routine water changes help stabilize the overall chemistry of the aquatic system and dilute out unwanted build-up of algae promoting nutrients.

    Not just any water will do.  We as reef hobbyists and professionals have discovered simple yet efficient ways of simplifying and correctly changing regular portions of salt water in our prized glass houses filled with precious sea critters.  First and foremost, the source water, which is the water prior to adding salt, should be completely free of all nutrients and contaminants prior to performing any water change. Performing improper water changes with nutrient-laden contaminated source water will only compound problems within the aquarium.    While freshwater aquariums will tolerate tap water with a commercial dechlorinator conditioner, our reef aquariums deserve better, do they not?  Tap water is generally considered UNSAFE.  Period. We don't recommend using tapwater in your reef aquarium at all, not even with a commercial dechlorinator.  Some of the unpleasant intruders contained in tapwater include pesticides, chlorine, ammonia, copper, chloramine, nitrate, phosphate, and silicate.  (and undoubtedly many more that we can't pronounce- hence the water cooler and paper cups in the corner of the office...)  In order to make the perfect potion of seawater, Aqua Dreams recommends starting with Reverse-Osmosis DeIonized fresh H20.  This is the purest form of water, with the least amount of unwanted nutrients and contaminants.  DeIonizer's alone work well for a smaller tank, but they are expensive to replace and don't last very long.  Reverse Osmosis ("RO Units") Units are the most economical long-term solution to cleaning our tapwater and rendering it REEF SAFE, i.e. perfectly clean enough for our colorful salty pets.  Reverse Osmosis DeIonization units ("RO/DI Units") are the ultimate in water cleaning technology and your best choice for "ultra" clean source water.  Bottled water (who knows whats really in the bottle or where it came from) and Distilled water (has prolonged contact with metals during the distilling process) are less desirable options.  Aqua Dreams offers RO/DI water for sale in our retail store, as well as our WCP (Water Container Program) for anyone interested in purchasing clean source water for their water changes.   For larger aquarium owners and customers that don't live nearby, we offer several reliable, quiet, and efficient RO units for home or office use.  Call us or email us your questions or purchase them right here at Aqua-Dreams.com.  

    Once we have a pure source of H20, we will need a storage and mixing vessel.  The hobbyist can decide what is best for their particular situation, buckets, glass or acrylic tanks, plastic barrels, rubbermaid storage containers etc. are all excellent choices.  Be sure to add a high quality salt mix that contains no phosphate and mixes up with seawater or higher levels of Magnesium, Calcium, and alkalinity.  We recommend a power head or small pump, added to the mixing/storage vessel, to keep the water moving, oxygenated, and to assist in the dissolving of the salt mix.  ALWAYS  mix saltwater at least 1 hour prior to performing the partial water change.  This is very important as the marine salt takes time to dissolve and achieve equilibrium before adding the water to your aquarium.  Be sure to check & adjust the temperature and salinity of the water-change water to match your tank- obvious but often overlooked!!  Never add 60 degree saltwater to a 78 degree tropical tank, this will drop the temperature in your main display and cause the fish and corals to exhibit temperature stress, leading to possible disease outbreaks.  Use a sumbersible heater in the mixing vessel if necessary along with a reliable thermometer- and don't add the water to your tank until the temperature is exactly the same as the main display. If you need to adjust your salinity, the most effective way to do so is by adjustin the salinity of the water change water to slightly higher or slightly lower than your tank, to achieve the desire change in salt level.  Never change the salinity by more than 1 or 2 points at a time, doing so can trigger unwanted responses and stress from the tank inhabitants. 

    So we've got clean source water, the correct temperature, an accurate salinity, and good circulation in our storage container, now lets change some water!  Be sure to shut down heater and circulation pumps in the main aquarium prior to removing water.  Use a clean, clear, 4-5 foot section of tubing and start a siphon into a bucket.  Use the tubing like a vaccuum to remove excess detritus from the crevices in the live rock or pockets of dirt resting in the sand bed.  Never completely disturb live sand beds, run the siphon tube over the surface just close enough to remove settled detritus only.  A turkey baster is often a handy tool during a water change to assist in the removal of excess algae, detritus and fish waste, (just don't let your spouse see you sticking it back in the holiday drawer!)  Be careful not to remove too much water, generally 25-33% is standard- and be sure you don't remove more water than you have recently prepared.  Now connect the tubing to the pump in your storage device and simply pump the new water into the tank.  Be sure to unplug the heater in the storage vessel, if necessary.  Once the tank is refilled, start up your pumps and adjust the water level.  Any cloudiness should clear within a few hours, clean mechanical filters and skimmer after the water change.

     The frequency of water changes is often a major topic of discussion.  Aqua Dreams recommends routine water changes using the methods described above.  The average recommended water change is 25-33% monthly.  However, many hobbyists perform smaller water changes more frequently such as every week or every other week.  Increase water changes during periods of curing live rock, or after power outages, overfeeding, or any other issue that disrupts the biological cycle of the tank.  

TOPPING OFF EVAPORATED WATER  Remember, topping off low water levels due to evaporation is not the same as performing a water change.   Topping off will need to be done on a regular basis in between water changes as water evaporates.  It is important to keep salinity from changing and allowing the pumps and filters to operate as normal, however, adding top-off water is not the same as performing a water change- where water is removed and replaced, rather than just topped off.  Be sure when topping off to use RO/DI water with a ph / alkalinity buffer added. RO/DI Water tends to have a low ph, since the filtering process removes minerals.  Adding salt to the RO/DI water during a water change will bring the ph to the correct level.  However, when topping off with fresh water- ph alkalinity buffer is essential to re-mineralize the fresh water bringing the ph up to seawater levels, so as to prevent the ph & alkalinity levels in the main aquarium from dropping.  Usually salt is not added to evaporation make-up water, since salt does not evaporate.  Making the mistake of adding salt water instead of buffered fresh water when replacing evaporated water can lead to abnormal elevated salt levels and stress to the aquarium inhabitants.   

We hope you find these resource helpful.  Please tell a friend about Aqua-Dreams.com.  Call the retail store during normal business hours or email us if you have any other questions!