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Water Care


December 13, 2018 | By Tom Sarac

by Tom Sarac

It’s no secret that the oceans dominate our planet. They are a huge fascination for many of us, especially when it comes to tropical marine reefs. As the saltwater segment of the home aquatic hobby continues to steadily grow each and every year, I’ve composed some helpful Do’s, Don’ts and How To’s to help aspiring reef aquarists successfully recreate a stabile and healthy environment.


With the ocean containing approximately 1,300,000,000,000,000,000,000 litres of water (343 Billion gallons), our home aquariums pale in comparison. However, this makes it all the more important for us to ensure we intervene by maintaining stabile water conditions for the sea life we keep, grow and nurture.

Water level. Be as consistent as possible and this supports constant salinity levels. The ocean is stabile and comprises the vast surface majority of our planet. Its big and doesn’t change that easily, but if it does, we’ve seen the disastrous effects this has on the world’s reefs. Think about it in terms of your aquarium.

Temperature. Environmental conditions within your home and support equipment on your aquarium all contribute as heat sources. If you cannot maintain a consistent water temperature between approximately 76øF (24.4øC) and 80øF (26.66øC), invest in a chiller or address whatever you need in order to keep your aquatic system in that ideal temperature range.

Water quality. If your tap water has measureable phosphate or nitrate content, you should invest in an R/O (reverse osmosis) water purification system. Some tap water is loaded with organic waste and particulate, which will create havoc in your marine aquarium. If an R/O filter system pre-filter cartridge goes deep brown within a few months, you can consider that investment a game changer for your reef. They are relatively inexpensive these days, easy to install and will give you water that will make any drink containing H2O taste better. To control levels of phosphate, nitrate and/or organics that accumulate in marine aquariums, it’s strongly recommended to use Fluval Sea Total Clear and Phos Clear to eliminate and prevent these unwanted elements from causing unwanted effects.

Water testing. Specific gravity, calcium, magnesium, alkalinity and pH should be checked bi-weekly. These are all key parameters that need to be kept within the right range to ensure you’re providing an ideal living environment. Various aquarium conditions will affect these parameters differently – heavy coralline algae growth will deplete calcium and alkalinity levels quickly, which is surprisingly similar to a full blown sps reef.

Water changes. A 15?20% bi-weekly change is a good target. Within the constraint of your aquarium providing only a limited volume of water vs. bio-load, it supports the argument that you must maintain water quality through regular water changes. If your aquarium is more heavily stocked and/or you are a heavy-handed feeder, consider increasing the % of water change. Also, before removing the water, it’s a good time to take a strong circulation pump or power head and use its output to power clean soft LPS and polyp-covered surfaces of various debris. Organic waste and debris gets easily lodged between large polyps. You’ll be surprised how much debris is liberated from a large pagoda coral, for example, then remove the % of water for your regular partial. A final and very important point for water changes is to make sure the newly prepared water delivers an ocean-like pH of 8.1 to 8.2. High pH values found in some high-alkalinity marine mixes can cause corals to stress and slime.


There is a vast selection of fish and coral to choose from when stocking a marine reef. For those of you who wish to make coral your priority, keep in mind you’ll have a considerably narrowed down list of fish species top choose from. On the other hand, some of us have been known to take chances and create a part of the reef for a specific fish we want to keep. In that case, make sure you understand the risk you will pose to the coral.


If you’re stocking a reef tank, make sure the fish are relatively coral-safe as there’s nothing more de-stabilizing than having to tear it down. This could happen if you take a chance on a species that ?can? spend its day nipping and picking on coral, therefore, keeping polyps closed.

Quarantine all new arrivals. A disease outbreak is very de-stabilizing and can mean a reef teardown to save fish.

Don’t overfeed. Excessive food will introduce phosphate and nitrate. Keep fish well fed, but not stuffed. Rinse frozen foods with cold water in a fish net before feeding.

Don’t overstock the tank. Less is more. Fish will behave more naturally and be less prone to stress. To reduce aggression towards new fish introductions, you can float them in a see-through container that allows water circulation for a few days while the other fish get used to seeing them. You can time the release to occur during a water change or other maintenance activity.

Remember that some fish, while coral-friendly, may be experts at consuming shrimp and other desirable invertebrates. Do some research and know as much as possible about the species you want to stock.


When adding new coral, make sure you initially position it where neighboring corals will not harm it (or vice versa). Coral grows – consider this when you position new coral or be prepared to take some losses. Also, try and understand the light levels that coral has grown and lived under and position it accordingly. If they are newly exported coral, go slow. Start at lower levels in your reef and take your time placing it where that species should do well in terms of light intensity and water movement.

As corals grow, be prepared to prune some of them back. This will help you avoid some of the negative consequences such as light-reduction suffered by some species. This will also prevent longer term large teardowns, which can be really stressful to the animals.


Make sure both live rock and coral are free of them.

  • Aptasia. Common stinging pests that multiply quickly and need to be eliminated and avoided at all costs. There are certain products on the market that work effectively against them, but trust me when I say you’d much rather take preventative than reactionary caution in this case.
  • Red bubble algae (Botryocladia). Very bad for your aquarium, so make sure to remove it on sight.
  • Hair algae. Bristletooth tangs as well as other species will effectively eat it. Snails, reef hermits and a variety of urchins can all be effective. Many urchins will devour coralline algae as well, which I consider ok since I found that my alkalinity and calcium levels remain more consistent that way. Check water quality and make sure nothing has been compromised in terms of nitrate of phosphate levels. If you’re using R/O water, it might be time to consider replacing filter media.
  • Roundworms. Sometimes seen on Elegans coral. Remove the coral and bath it in a commercial iodine-containing product.
  • Crabs. In general, get rid of them on sight and make a serious attempt to do so. Many beautiful corals have been ravaged by crabs that may take you a long time to discover.
  • Mantis shrimp. A dedicated predator that can take out many live forms in your reef.
  • Bristleworms. To be safe, remove them and use traps to do so.
  • Acropora ?Red Bugs?. The very small pests appear as a half millimeter long ?mite-like? red dot and are very damaging to these sps coral. Let’s also not forget small coral-eating nudibranches that are best observed during night-time hours. Small white spots and patches can be eventually noticed in areas where the nudibanch has consumed part of the coral tissue.


Thanks to fact we now rely on live rock for biological inoculation and support of our marine reefs, we’ve simplified matters when it comes to equipment. The key is to look after support equipment like sump pumps, circulation pumps, skimmers and lighting with some regularity so we don’t get caught by surprise. The point here is stability.

Protein Skimmers. Arguably the most essential piece of support equipment after lighting. The skimmer strips marine water of dissolved organics and fine particulates, significantly purifying water and preventing further breakdown. To keep things running smoothly and support the nutrient-poor conditions we strive for in a reef, regular cleaning of impellers and submersed motors are essential to keeping you skimmer performing at top capacity. Removal of pumps and soaking in a vinegar/water solution can dissolve coralline algae and ensure impellers and pump housings remain unaffected by it. Equally important is ensuring air inlet paths are kept free of salt accumulations so the right ratio of air-to-water can be allowed into the skimmer for proper operation. On a regular basis, take a few cups of R/O water and let the skimmer pump ingest it via the air inlet. This will support stabile consistent air volume into the skimmer. Cleaning the neck and cup regularly will also keep the skimmer working the way it was designed to.

Sump Pumps. These units operate in the tough environment of a marine sump. Air cavitations are not conducive to long pump life, so consider fitting the least restrictive elbow to the inlet and allow water pick up just above the bottom of the sump. This will prevent a vortex at the surface and unwanted air intrusion into the impeller chamber, therefore allowing for a quieter operation. As mentioned this is a harsh environment for a pump. Make sure the sump pump is given a mild vinegar bath every once and a while. Use a brush to clean out the impeller and impeller well properly. If the unit is ?hard plumbed,? then inspecting the easily-Accessible pipes and fittings for accumulated calcareous deposits will be necessary. Reduced flow and proper drainage diminishes over time.

Circulation Pumps. Given their plastic bodies and the rate at which coralline algae grows on this material, it’s easy to overlook grills becoming plugged with the ?purple stuff.? Impellers and pump housings on these pumps need to be cleaned regularly – a key consideration in maintaining proper water movement for coral health and condition. If you have these pumps connected to a switching device, make sure you verify the pump’s operation regularly. These devices will shorten the lifespan of many circulation pumps and when just one of them fails you may not notice it for a while.

I know all this information may seem overwhelming at first, and yes it can be challenging and typically more of an initial investment than a freshwater tank, but there just isn’t any other type of aquatic environment more fascinating and rewarding in my opinion than a marine reef. In time, and with proper supervision and regular maintenance, these set-ups will mature and inherently become more stabile for you to enjoy. I sincerely hope you found this article helpful, and I wish you great success in creating your own marine reef… the options are as limitless as the pleasure of operating one.


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