Eheim Pro 4+ 350T Thermo External Filter
Eheim Professionel 4+ Canister Filter: A Six-Month Verdict
As any seasoned fishkeeper in the UK knows, choosing the right filter is one of the most crucial decisions for a healthy aquarium. I was recently sent the Eheim Professionel 4+ to test and review for my heavily planted 240-litre community tank. After running it for six months, it feels like the right time to share a proper long-term review. Eheim has a formidable reputation, but the price tag that comes with their premium gear always begs the question: is it truly worth it?
First Impressions and Setup
Straight out of the box, the build quality feels reassuringly solid. German engineering is a bit of a cliché, but it applies here. The plastics are thick, the locking clips are robust, and everything fits together with a satisfying precision. It’s a handsome, square-shaped unit in anthracite grey that sits neatly in the cabinet without the wasted space you get with a round filter.
The box comes with everything you need to get going: all the necessary pipework, a spray bar, an intake pipe, and, most importantly, all the official Eheim filter media. This is a huge plus, as you’re not immediately spending extra on media. The included Substrat Pro and Mech Pro are top-notch materials.
Setting it up was fairly straightforward. The instructions are clear, and the hose connections have a safety adapter that prevents you from accidentally detaching them and flooding the living room – a feature my partner was very pleased about. The only slight faff was getting the hoses connected, as they are quite rigid at first. A quick dip in some hot water softened them up and made the job much easier. The priming system, a large push-button on the top, worked a treat. It took a good few pumps to get the siphon going, but once it started, it filled quickly and without any fuss.
Performance: Silence is Golden
Once plugged in, the first thing I noticed was the silence. Or rather, the lack of it. For the first hour or so, there was a noticeable hum and the sound of trapped air working its way out. I was a bit concerned, but by the next morning, it had settled into being virtually silent. Now, six months on, the only way I know it’s running is by seeing the gentle flow across the surface of the water. It sits in my living room, and you genuinely cannot hear it over the ambient sound of the house. For me, this is one of its biggest selling points.
Water clarity has been consistently exceptional. My tank is crystal clear, and water parameters have remained stable, even with a fairly high bioload. The flow rate is powerful but easily adjustable, so you can tailor it to the needs of your fish and plants without creating a whirlpool.
Key Features in the Real World
The Professional 4+ comes with a few standout features, but the two most practical are the large pre-filter and the ‘Xtender’ function.
- The Pre-filter: This sits right at the top of the canister and catches the largest bits of debris. It means you can give the pre-filter a quick rinse every month or so without having to disturb the main biological media baskets. This has massively extended the time between full cleans.
- The ‘Xtender’ Dial: This is a clever little dial on the filter head. If you notice the flow rate dropping because the fine filter pad is getting clogged, you can turn this dial to bypass it slightly. This keeps the water flowing over the biological media, maintaining your tank’s cycle and buying you an extra few days before you absolutely have to do maintenance. I’ve used it once when I was away for a weekend, and it worked exactly as advertised. It’s not something you should rely on, but as an emergency feature, it’s brilliant.
Maintenance After Six Months
I did my first full clean after about five months, prompted more by curiosity than a drop in performance. The design made it a doddle. The safety adapter lets you disconnect all the pipework in one go with no spills. The canister is a bit heavy when full, but the recessed handles help. Inside, the media baskets lift out easily, and the ‘Easy Clean’ grid makes rinsing the media simple. Thanks to that pre-filter, the biological media was surprisingly clean. The whole process took less than half an hour.
Final Thoughts
After six months of continuous use, the Eheim Professional 4+ has been nothing short of flawless. It’s a premium filter, and it certainly has a premium price tag to match, which will be the biggest hurdle for many. However, I genuinely believe you get what you pay for.
What I Like:
- Excellent filtration performance, keeping water pristine.
- Top-quality build and materials.
- Smart features like the pre-filter and ‘Xtender’ function are genuinely useful.
- Comes complete with high-quality Eheim media.
- Very easy to maintain.
What I Don’t Like:
- The high initial cost.
- The included hoses are a bit stiff and could be slightly longer.
In conclusion, if your budget can stretch to it, the Eheim Professional 4+ is a fantastic investment for any serious aquarist. It’s reliable, powerful, whisper-quiet, and designed with the user in mind. It has performed impeccably for the last six months, and I have no doubt it will continue to do so for many years to come. It’s a top-tier filter that justifies its price through sheer quality and peace of mind.
⭐⭐⭐⭐☆ (4/5)
At time of writing the Eheim Professional 4+350t is available at around £319
