Aquarium Maintenance:
The Complete Guide

The most common cause of fish health problems we see when we take over a client's existing tank is not disease — it's deferred maintenance. Nitrate accumulates silently, filter media gets overloaded, and fish live in slowly declining water quality for months before problems become visible. This guide tells you exactly what to do and when.

Water Changes — The Core of Aquarium Maintenance

A partial water change dilutes nitrate, replenishes trace minerals and removes dissolved organic compounds that test kits don't measure. Key principles:

• Always dechlorinate before adding water — use a product rated for chloramine if you're in London, East Anglia or the Midlands (see our UK tap water guide)
• Match temperature within ±1°C — cold water shocks fish, especially discus and other warm-water species
• Never change more than 30% at once in an established tank (except discus) — larger changes can destabilise the nitrogen cycle and cause pH shock
• Vacuum the substrate during water changes to remove detritus before it decomposes into ammonia

Professional Maintenance vs DIY

Many fishkeepers start maintaining their tank themselves and then join one of our plans — not because they can't do it, but because the consistency of a professional visit ensures nothing gets missed. Here's what our plans cover: