Common problems & solutions

Usually caused by: excess light + excess nutrients (nitrate/phosphate) from overfeeding or infrequent water changes

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Solution steps

1. Reduce lighting to 6–8 hours/day
2. Regular water changes and vacuum the substrate
3. Limit feeding
4. Add algae-eating animals or use an algaecide

Products / animals (Australia)

Usually caused by: high silicates in new tanks or tap water, low light, and an immature biological filter

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Solution steps

1. Very common in newly set-up tanks — usually fades as the tank matures and silicates are depleted
2. Manually wipe glass and decorations
3. Avoid excess light in low-tech tanks
4. If persistent, check for silicates in tap water and consider RO water or a silicate-removing resin

Products / animals (Australia)

Usually caused by: unstable or low CO₂, poor flow, and excess organic waste in planted tanks

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Solution steps

1. Improve CO2 and flow (planted tanks)
2. Spot-treat affected areas
3. Manual removal

Products / animals (Australia)

Usually caused by: stress from poor water quality, temperature swings, or introduction of infected fish

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Solution steps

1. Raise temperature gradually (if the species tolerate it)
2. Increase aeration
3. Treat with medication for the full course
4. Quarantine if possible

Products / animals (Australia)

Usually caused by: poor water quality, physical injury, or stress that allows opportunistic bacteria to take hold

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Solution steps

1. Improve water quality with water changes
2. Remove activated carbon from the filter
3. Treat with antibacterial medication

Products / animals (Australia)

Usually caused by: bacterial bloom in new or disturbed tanks, overfeeding, or excess dissolved organics

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Solution steps

1. Do not over-clean the filter in new tanks
2. Reduce feeding
3. Add beneficial bacteria
4. UV steriliser for persistent blooms

Products / animals (Australia)

Usually caused by: incomplete nitrogen cycle, overfeeding, overstocking, or filter failure

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Solution steps

1. Immediate 25–50% water changes
2. Stop or reduce feeding
3. Add beneficial bacteria
4. Use an ammonia detoxifier

Products / animals (Australia)

Usually caused by: infrequent water changes, overfeeding, overstocking, or inadequate plant/nutrient export

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Solution steps

1. Increase water-change frequency
2. Reduce feeding and stocking
3. Add live plants
4. Improve filtration

Products / animals (Australia)

Usually caused by: excess nutrients (phosphate & nitrate), insufficient export, and too much light or poor flow

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Solution steps

1. Reduce nutrients (phosphate and nitrate)
2. Increase export (skimmer + water changes)
3. Manual removal
4. Improve flow and reduce lighting

Products / animals (Australia)

Usually caused by: silicates leaching from new sand, rock or RO water during the first 1–3 months of a tank’s life

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Solution steps

1. Extremely common in new marine tanks (first 1–3 months) as silicates leach from sand, rock or RO water
2. Manually wipe or siphon surfaces
3. Ensure good flow and avoid excess light during the early stages
4. Use a silicate-removing resin on the RO unit or in a reactor if the problem persists after the tank matures
5. Once the silicate source is exhausted, diatoms usually disappear on their own

Products / animals (Australia)

Usually caused by: low flow, excess dissolved organics, and an imbalance of nutrients (often low nitrate with elevated phosphate)

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Solution steps

1. Improve flow
2. Siphon out as much as possible
3. Blackout 3–4 days if severe
4. Correct the nutrient imbalance

Products / animals (Australia)

Usually caused by: introduction of infected fish, stress, or temperature/salinity fluctuations

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Solution steps

*** Never treat the display reef with copper. Copper will kill coral and inverts ***

1. Move infected fish to a seperate 'hospital' tank for treatment and to reduce risk of infecting other fish
2. Treat with copper or an alternative
3. Leave the infect fish in quarantine for 6-8 weeks and where possible the display tank should not have any other fish to creat a break in the ich lifecycle

Products / animals (Australia)

Usually caused by: introduction of infected fish or sudden stress that allows a dinoflagellate parasite called Amyloodinium ocellatum to bloom. It requires urgent treatment

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Solution steps

*** Never treat the display reef with copper. Copper will kill coral and inverts ***

1. Extremely urgent — act fast
2. Move infected fish to a seperate 'hospital' tank for treatment and to reduce risk of infecting other fish
3. Treat with copper or chloroquine treatment
4. Keep fish isolated for at least 14 days after visible signs of infection are gone - the longer the better.

Products / Animals

Usually caused by: hitchhikers on live rock or coral frags that then spread in nutrient-rich conditions

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Solution steps

1. Inject individual polyps carefully
2. Prefer biological control in reef tanks
3. Avoid spreading by fragmentation

Products / animals

Usually caused by: overfeeding, insufficient protein skimming, lack of nutrient export, or decaying organics

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Solution steps

1. Increase water changes and skimming
2. Reduce feeding
3. Use phosphate-binding media
4. Grow and harvest macroalgae

Products / animals (Australia)

Usually caused by: high coral demand without adequate supplementation, or inconsistent dosing

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Solution steps

1. Test regularly
2. Dose two-part or all-in-one supplements
3. Keep parameters stable

Products / animals (Australia)