Reef Ramblings

Maintenance.

Water Changes.

From here on in it’s time to get into the habit of regular water changes. Aim to change 10 to15% of your water every one to two weeks; this will help keep your reef healthy by diluting potential pollutants and by replacing trace elements used up within the system. In the early days of a reef your water changes will most likely replenish the Calcium and Carbon being taken up by the few creatures inhabiting it; as you increase the number of animals the Calcium/Carbon demand will increase until you reach a point where water changes will no longer supply enough of these two elements. This will be covered further on, but for the moment, until this demand is demonstrated through measurement; water changes are all that’re required.

How to make up your water.

For mixing new salt water you’ll need a few items of equipment:

• A bucket or container made from food safe plastic of sufficient capacity to contain 10% of your tank volume e.g. 2.5 gal/12l bucket for a 25-gal/120l tank. Old aquarium salt buckets or home brewing buckets are ideal.
• An aquarium heater to warm the water (don’t look on this item as a luxury or as an unnecessary expense, think of it as an essential piece of spare equipment should your main tank heater fail and hence size it accordingly).
• Either an air pump or power head to mix the water (again you should look on it as an emergency spare).
• An aquarium thermometer.

An additional piece of equipment you might like to consider would be a RO unit to produce your own RO water. As many marine specialist shops now sell RO water you can miss this out if you want, especially with smaller tanks were your water requirements won’t be that high (at the time of writing, including water for evaporation top up, you’d spend about the same on water over a two year period as it would cost you to buy a RO unit based on 5 gal/22.5l a fortnight – it’s your choice!).

To mix your water:

• Add the required amount of RO water to the bucket (making sure heater is fully immersed).
• After about 15 minutes turn the heater on and start agitating the water with your air pump/power head.
• When the water is up to a temperature of 25ºc add your salt. As a guide I suggest 35 grams/ litre e.g. 350 grams for 10 litres of water.
  
• Leave to mix for 24 hours before using (don’t forget to turn the heater off and make sure the element‘s had a chance to cool prior to emptying your bucket).

Doing the water change:

There are lots of different ways of doing a water change, as far as I’m concerned, if there are no apparent algae problems just syphon the water out into a bucket using a length of 12 mm flexible hose.

If there is an algae problem it can be useful to do the syphoning with a length of air-hose. Using air-hose slows down the rate at which you take water from the tank allowing you to take your time syphoning out pest algae, this is particularly useful if you are trying to eradicate green slime algae or red slime algae (cyano-bacteria) where the pest species has a tendency to coat the rocks, sand, and glass. In can sometimes be a good idea to use a cup or jug to scoop water from the surface of the aquarium, especially if you are having problems with bacterial or algal films forming on the surface. Though if you do have these films forming it would be better to determine why and then make any necessary alterations to cure the problem.

When introducing the newly made up water – you did check the salinity first didn’t you? – Be careful to pour it in to a strong flow and not directly on to any of your corals. This is one of the pluses of having a sump; you can more or less just pour in the freshly made up water without worrying about this. After you’ve finished adding the new water it might be worth waiting 15 minutes or so to allow the water to mix, then double check the salinity in the aquarium, in case any adjustments need to be made. If the salinity is too high slowly add RO, say about a litre at a time maximum, again being careful not to pour directly on to a coral. If salinity is too low either mix up a small amount of water at a higher salinity and add that or if there’s only a small difference e.g. 1.024 when you want 1.025, let evaporation do the job for you, topping up with water of the required salinity at a later time to correct your water level.

Tim Hayes

Midland Reefs

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