Aquatic Water Quality 101: A Practical Guide to a Clear, Healthy Tank

Setting up (or rescuing!) an aquarium doesn’t have to be guesswork. If you understand water quality and use a handful of proven products, you can keep your fish and plants thriving with far less stress. In this guide, we’ll walk through the core Seachem tools we recommend for fresh and planted tanks and how to use them together for fast, reliable results.

 

Why Seachem?

Seachem has been a hobby staple for decades because their range is concentrated, effective, and predictable. Whether you’re cycling a new tank, dealing with cloudy water, or dialling in a high-energy planted setup, there’s a Seachem solution that slots neatly into your routine.

Quick picks:
• Dechlorination & detox: Prime
• Fast biological start & stability: Stability
• Long-life bio-media: Matrix
• Polish water & reduce organics: Purigen
• Plant nutrition: Flourish Comprehensive (+ Excel, Potassium, Iron)
• Balancing GH/KH: Equilibrium, Alkaline Buffer, Acid Buffer
• Cloudy water fix: Clarity
• Phosphate control (algae support): PhosGuard

The “No-Panic” Routine for New Tanks (Freshwater)

Goal: Safe fishless cycle (or fish-in emergency support) with minimal fuss.

1. Condition every drop: Dose Seachem Prime on tap water at each water change to remove chlorine/chloramine and detoxify ammonia/nitrite for up to 48 hours.
2. Seed bacteria: Add Seachem Stability daily for the first 7 days (and after any large clean/filter change).
3. Give bacteria a home: Load your filter with Seachem Matrix bio-media; its porous structure supports strong, stable colonies.
4. Polish and protect: Add a pouch of Seachem Purigen to absorb dissolved organics that cause yellowing/odours—your water looks “HD” and maintenance gets easier.
5. Test & top-up: Use your test kit 2–3× weekly. If ammonia or nitrite blip, dose Prime (detox) and continue Stability (bacteria support).

 

Clear-Water Troubleshooting (Cloudy, Green, or Tea-Stained)

Milky/cloudy: Often a bacterial bloom or fine particulates.

• Add Seachem Clarity (flocculant) and clean with mechanical filtration; keep Stability dosing steady.

Green tint & algae hints: Extra nutrients/photoperiod.

• Use Seachem PhosGuard to pull down phosphate; adjust lighting to ~6–8 hrs; ensure consistent fertiliser balance if planted.

Yellow/tea colour (tannins/organics):

• Rinse wood; run Seachem Purigen to remove dissolved organics and restore sparkle.

 

Planted Tank Basics: Simple, Balanced Dosing

Healthy plants outcompete algae, so feed them properly.

• Base fertiliser: Seachem Flourish Comprehensive 1–2× weekly for micros.
• Carbon supplement: Flourish Excel (liquid carbon) boosts growth—dose daily or every other day per label. Note: Be cautious with sensitive plants (e.g., Vallisneria) and never exceed the dose, especially with shrimp.
• Macros & iron: Add Flourish Potassium and Flourish Iron if you see stunting or pale new leaves.
• Substrate nutrition: Root tabs for heavy root feeders (swords/crypts).

 

Hardness, pH & Buffering (GH/KH) — Keep It Steady

Fish and plants love stability. If your tap water is very soft or you use RO:

• Remineralise GH: Seachem Equilibrium (freshwater) for robust plant growth and fish health.
• Set KH/pH: Seachem Alkaline Buffer (raises) and Acid Buffer (lowers) to reach your target pH with proper alkalinity. Always adjust slowly.

Ready-Made “Recipes” for Common Problems

Ammonia spike after adding fish

• Prime (detox), Stability (daily for 7 days), test daily, light feeding, maintain Matrix.

Persistent smell/tea colour

• Swap/refresh Purigen (regenerable), increase pre-filter floss, review feeding.

Algae creeping in

• Reduce light to 6–7 hrs, ensure balanced Flourish dosing, add PhosGuard, improve flow, remove decaying leaves.

Plant melt in soft water

• Dose Equilibrium to lift GH; ensure Potassium/Iron support; keep CO₂ or Excel consistent.

 

What Size Should I Buy?

Seachem concentrates go far. As a rule of thumb for Prime and Stability, 250 ml suits nano tanks (up to ~60 L) for months; 500 ml+ offers better value for 100–200 L community tanks. Media like Matrix is typically 250 ml per 200 L of water (stack more for heavy stock).

Quick add to basket: Seachem Prime 250 ml, Stability 250 ml, Matrix 1 L, Purigen 100 ml, Flourish Comprehensive 250 ml

 

Why Buy from Us

At Aquatic Addiction, we stock the full Seachem range with UK-fast dispatch, fresh dating, and real-world advice. Need a tailored dosing plan? Message us with your tank size, stock, and water test results and we’ll help you pick the right bottles first time.

👉 Shop Seachem Bestsellers

 

Frequently Asked Questions 

Is Seachem Prime safe for shrimp and snails?
Yes, when used as directed. Avoid overdosing and ensure good oxygenation—especially in nano tanks.

Can I use Prime and Stability together?
Absolutely. Prime detoxifies ammonia/nitrite, while Stability supplies bacteria to process them—ideal during cycling or after filter disruption.

How often should I replace Purigen?
When it turns dark brown/black and stops polishing water. You can regenerate it with bleach per Seachem’s instructions; rinse/dechlorinate thoroughly before reuse.

Do I still need water changes if I use Matrix and Purigen?
Yes. They reduce waste and polish water, but water changes remove nitrate and replenish minerals for plant and fish health.

Can Flourish Excel harm plants or inverts?
Used correctly it’s widely tolerated, but some species (e.g., Vallisneria, certain mosses) can be sensitive to high doses. Start low, never exceed the label, and observe livestock.

 

Disclaimer: This guide is for general information only, always follow manufacturer instructions and monitor your water parameters; Aquatic Addiction accepts no liability for any loss or damage arising from use or misuse of these products.