Your Path to a Reef Aquarium: The ReefManager How2Start Guide

The aquascape is the foundation of your aquarium. The modern approach favors starting with dry rock that you design yourself. This gives you full creative control and crucial biological advantages.

The basic idea: The less rock you use, the faster it can be biologically "activated" by the aquarium. Less mass also means that potentially stored substances (like phosphates), or the absorption (saturation) of them, have less impact on your water parameters, leading to significantly fewer fluctuations in the start-up phase.

• The Modern Approach: Dry Rock for a Clean Start Instead of using large, massive boulders, the trick is to specifically break down the dry rock. Be bold and use a hammer and chisel! The goal is to glue 2-4cm pieces of stone together with superglue and activator to create an airy structure. Then, rinse it well before placing it in the tank...
• The Philosophy: Less is More Your goal is to create maximum surface area for corals with the least possible rock mass. Think in terms of pillars, overhanging plateaus, and free-floating structures. An airy structure not only looks better but also has tangible advantages - your corals will quickly shape the reef in this environment.
• Stability and Structure Build your reef outside the aquarium on a piece of cardboard the size of your tank's base.
  • Base: Start with a few stable base rocks.
  • Fixation: First, connect the broken stones into arches and then into 3D structures. For delicate connections, superglue gel combined with an activator spray is suitable. Make sure everything is solid.
  • Tip: For "floating" structures, you can mount the stones on thin acrylic rods and hide them within the reef.
• Flow and Open Space A minimalist setup is perfect for flow. The water can circulate around the reef from all sides, preventing "dead zones" and maximizing the removal of waste products. Plan for channels and caves. This way, you don't "stress" corals in one spot with too much flow while another area has too little.
• Planning Space for Corals The many plateaus and levels create ideal placement areas. Think now about where different corals will go later: Where is there a lot of light for SPS? Where is it shadier with moderate flow for LPS or soft corals?
• Distance and Substrate Be sure to maintain a 5-10 cm distance from all glass panels to make cleaning much easier later. The substrate (sand) is added only after the reef structure is complete and stable; starting without substrate is preferable.

Carefulness here is crucial for later success. There are two proven methods for mixing saltwater.

Method A: Mixing Directly in the System (for large tanks)

• Fill with RO water: Fill the main tank and the sump with pure RO water.
• Add salt: Add the marine salt slowly and in portions directly into the sump, ideally in a high-flow chamber (e.g., the return pump chamber). An additional small powerhead in the sump will speed up dissolution. Important: Never add salt directly to the main tank!
• Start equipment: Turn on all pumps (return pump, flow pumps) and the heater to distribute and dissolve the salt.

Method B: Mixing in External Containers (recommended for precision)

• Prepare water: Mix the saltwater in separate, food-safe containers (e.g., buckets or barrels) of a known volume.
• Calculate salt amount: Follow the instructions on the salt packaging exactly (e.g., 38 grams per liter). Use an accurate kitchen scale. Double-checking your calculation is mandatory! A simple calculation error can ruin the entire start-up phase.
• Dissolve: Add the weighed salt to the RO water and let it dissolve completely with a small powerhead and a heater. The water should become clear.
• Fill with prepared water: Fill the aquarium with the fully mixed and heated saltwater.

Final Check & Equipment Start (applies to both methods)

• Measure temperature & density: Once the salt is completely dissolved and the temperature is stable (target: 24-25°C), measure the salinity. If you have weighed the correct amount of salt and have not made a mistake with the volume, it should be correct! When in doubt, it's better to measure again. Use a calibrated refractometer or hydrometer.
• Adjust: If the density is too low, dissolve a little more salt in a separate container and add it. If it is too high, carefully dilute with RO water. Your target value is a density of 1.023-1.024 g/cm³ or a salinity of 34-35 PSU.
• Start skimmer: Now turn on the skimmer as well. It is normal for it to "over-skim" or not skim at all in the first few days. Adjust it to skim very little to none at first - you want to keep the nutrients in the system. Readjust it over the following days.

Light and movement are essential for the reef climate.

• Lighting: Start with a very short lighting period (e.g., 10-11 hours per day) and low intensity. Initially, 1/4 watt per liter of active power (LED) is great for LPS, 1/3 watt per liter for SPS.
• Flow: Adjust the flow pumps so that the entire tank is well circulated. For LPS, a gentle, slow water movement is sufficient. If the flow is too strong, the animals will not open up.

This is the most important phase of the entire start! Mistakes made here often lead to the death of corals or a months-long odyssey with algae plagues. The goal is to create a stable biological balance from day one.

Step 1: "Seeding" the System

A sterile tank needs life. The fastest and safest way to start the nitrogen and nutrient cycle is to introduce established bacterial cultures.

• The Ultimate Turbo-Start: Get "gunk-filled" filter floss or filter sponges from a well-running, healthy saltwater aquarium. Squeeze this "dirt" out in the sump or directly in the aquarium. It looks unsightly, but it is pure biological gold and starts the cycle immediately.
• Alternative: High-quality bacterial starters from a specialty store. These are a good supplement or alternative if you do not have access to established filter material. Follow the instructions carefully.

Step 2: Controlled Nutrient Supply from the Beginning

The biggest mistake in the cycling phase is to let the first corals starve. A brand-new system has no nutrients (phosphate and nitrogen), which corals absolutely need to survive. We must therefore supply them in a controlled and low-dose manner.

• Nutrient Sources: There are excellent products specifically developed for this purpose that provide phosphate (P) and nitrogen (N) in a stable form (e.g., from Osci-Motion or other manufacturers).
• The Golden Rule: Dose according to the instructions, usually the same amount of both components (P and N).
• Measure and Adjust: Measure the phosphate value (PO4) every other day with a high-resolution droplet test (e.g., from Hanna).
• The Goal: Adjust the daily P/N addition so that the phosphate value remains stable at approx. 0.05 mg/L. If it rises, reduce the dose. If it falls, increase it slightly.
• Why this is so important: This method prevents nutrients from accumulating uncontrollably (which leads to algae) or the corals from becoming malnourished (which leads to bleaching and death). You create a stable, low-nutrient, but not nutrient-limited environment from the beginning – the perfect environment for healthy corals.

What Happens in the Background? (The Classic Nitrification Cycle)

While you are controlling the nutrients, the classic cycle runs in the background. However, through "seeding" and controlled supply, it proceeds much more gently and without dangerous toxin spikes.

• Ammonia (NH3/NH4) -> Nitrite (NO2) -> Nitrate (NO3): Established bacteria convert these substances so efficiently that you will ideally see hardly any measurable ammonia or nitrite peaks.
• Duration: With this method, the critical phase is often shortened to 2-4 weeks. The tank is "ready" as soon as your nutrient dosage is stable and you can reliably maintain the PO4 value.
• When to add the first corals? As soon as the PO4 value has been stable at your target of 0.05 mg/L for a few days, you can start with robust, simple corals.

This is perhaps the most important point for long-term success: The quality of your first corals significantly determines your motivation and the further course. A bad start with sick animals often leads to frustration.

• The Right Time: Start stocking the aquarium with corals after 1-2 weeks (as soon as nutrients are stable and easily detectable).
• The Source is Crucial: It is best to buy your corals privately from experienced aquarists or from a dealer you absolutely trust.
• Look Closely: Ask to see the mother colonies and the holding tanks. Make sure they are free of Aiptasia, algae plagues, or other pests.
• Get Advice: A good seller will ask you how your tank is running and recommend animals that fit your system. Don't let them sell you half-dead or freshly imported, stressed animals.
• Health Check: A healthy coral has fully expanded polyps (if the species allows), vibrant colors, and no injured or dissolving tissue.

Algae are a normal part of biological development. However, if you follow the previously described method of controlled nutrient supply, you will find that usually no or only very weak algae phases develop. This is a sign that your system is starting in balance.

Dealing with Emerging Growths

It can still happen that light growths appear. Quick action is the key to success here.

• Diatoms (brown dust): Often appear as the first, fine brown coating. They feed on silicates in the water and usually disappear on their own after a few days to weeks.
• Green Growths & Hair Algae: A sign of available nutrients. This is where your "cleaning crew" comes into play.
• Cyanobacteria (red/dark slime algae): An indicator of a biological imbalance. Siphoning them out and checking and stabilizing the nutrient values (P/N) is the first step here.

The First "Cleaning Crew" (immediately as needed)

Don't wait until the algae get out of hand! As soon as you see the first tiny green growths on the rocks or glass, it's time for the first inhabitants. The prerequisite is that your nitrite value (NO2) is no longer detectable.

The Principle of Food Competition: It is extremely important to introduce the appropriate predators immediately when the first growths appear. This prevents the algae from taking over, establishing themselves, and "stealing" the vital nutrients from the corals. You create natural pressure on the algae from the very beginning.

• The First Settlers: Immediately add some Turbo snails. They are extremely efficient algae eaters and keep the first growths in check.
• With increasing hair algae: If you notice that longer green algae are forming, Mithrax crabs are an excellent addition. They specialize in this type of algae.
• All-rounders: A small group of hermit crabs helps to clean up food scraps and detritus and keeps the substrate clean.

When do the fish come? (Patience is key)

Fish introduce a significant and difficult-to-control amount of nutrients into the system through feeding. Therefore, an important rule applies:

• Add fish much later! Wait until your first corals are well established and have started to show visible growth. Your system should be running stable for several weeks beforehand.
• The Nutrient Strategy: It is always easier to dose nutrients specifically and separately (as practiced in the start-up phase) than to lower high nutrient levels caused by fish food. A high nutrient content almost always leads to algae problems. Start with a few fish and monitor your water parameters closely.

If you have followed everything so far, further success depends on two core parameters. They are the absolute be-all and end-all.

• Stable Nutrients (PO4): Your phosphate value must be stable. Fluctuations are pure poison for corals. Whether you keep it at 0.03, 0.05, or 0.08 mg/L is less important than the fact that it is constant. Daily, automated dosing is the key here.
• Stable Carbonate Hardness (KH): A stable KH value is just as important. Fluctuations stress corals extremely and can lead to tissue loss. Measure regularly and adjust your dosage to consumption.

Let it be said: If these two values are not stable, your corals will die. If they are stable, you have already won half the battle for a successful reef aquarium.

• Patience: Add fish only when your corals are established and growing. Every fish increases the nutrient load.
• Go Slow: Add fish individually or in small groups several weeks apart to allow the biology to adapt.
• Appropriate Selection: Choose fish that are suitable for the tank size and for each other.

Corals, bacteria, and the rock immediately begin to consume nutrients. A deficiency in the start-up phase is one of the most common reasons for failure. Therefore, this is your first and most important step:

• Stabilize Phosphate (PO4) & Nitrogen (N): As described in the cycling phase, your main task is to keep PO4 and N at a low but stable level.
  • Measure: Initially, measure the phosphate level (PO4) every other day.
  • Target Value: Keep PO4 stable at approx. 0.05 mg/L.
  • Adjust: Adjust the daily dosage of P/N solutions until the value remains stable over several days. This is the foundation for everything else.
• Filter Floss - The Game Changer: Use filter floss in the sump from the very beginning. It is an excellent settlement substrate for bacteria and helps to keep nutrients stable and available.
  • Care: Do not remove the floss completely! If it gets clogged, loosen it up or remove only a part and add fresh floss. This way, you preserve the valuable bacterial culture.

Trace elements are essential for the coloration and health of corals and are also consumed from the beginning.

• Start Basic Supply: Begin immediately after the tank start with a basic trace element supply (e.g., Osci-Motion Trace Starter or similar products).
• Set Dosage with the ReefManager App: Use the ICP section of the ReefManager App to correctly set the dosage for your tank volume. Instructions and videos can be found directly in the app.
• First ICP Analysis: Perform the first ICP analysis after about a month. This will show you exactly which elements have been consumed.
• Algorithmic Adjustment: Enter your ICP results into the ReefManager App. The algorithm calculates the exact adjustment of your dosage to bring the trace elements back to the target level and keep them stable in the future.
• Important: In the first 3-4 months, stronger fluctuations are normal as the biology is still stabilizing. This is not a problem. Regular ICPs (every 2-3 months) will help you maintain control.

The main building blocks for the coral skeleton (carbonate hardness, calcium, magnesium) only become relevant when your corals begin to show visible growth.

• Carbonate Hardness (KH) First: As soon as you notice visible growth, start measuring the KH value weekly. If it drops, begin dosing (e.g., with Balling salts) and adjust the value to approx. 7.5 dKH.
• Calcium (Ca) Next: When you are dosing a significant amount of KH solution, it is time to also measure the calcium value and adjust the dosage to keep it stable at approx. 430 mg/L.
• Magnesium (Mg) Last: Magnesium is consumed the slowest. Measure it monthly at first and adjust the dosage as needed to keep the value at approx. 1400 mg/L.

In a modernly supplied reef aquarium, regular, large water changes are often no longer necessary and can even disturb the painstakingly built stability.

• Principle: Perform a water change only if the tank's biology is not "starting up," you are fighting an inexplicable plague, or an ICP analysis shows a massive accumulation of a pollutant.
• If so, then small: If a water change is necessary, limit yourself to small amounts of 5-10%.

Marine aquaristics is a continuous learning journey. Use the available resources to expand your knowledge and get quick help with problems.

• ReefManager Community: Visit the ReefManager WhatsApp group. Here you will meet many experienced aquarists and receive valuable tips and first-hand support.
• ReefManager AI: Use the AI integrated into the app for further information, problem analysis, or to ask specific questions.
• Learn to Observe: Your most important tool is daily observation. Learn to read the signs of your aquarium and react to changes early.