Square Water Tank Green – 200L, 300L & 520L with Lid for Irrigation

The Square Water Tank is the definitive upgrade your grow room needs to stop depending on buckets and constant trips to the tap. This rigid green polyethylene reservoir is designed to store large quantities of water or nutrient solution, keeping it clean, stable, and ready for your plants whenever they need it. It is the backbone of any serious irrigation setup, offering durability and the peace of mind that comes with having a reliable water reserve.

Why your current watering routine is holding you back

Are you still mixing fertilizers bottle by bottle every time you need to water? Or worse, are you running out of prepared water halfway through the process? Relying on small containers or direct tap water without letting it sit is a rookie mistake that consumes your time and destabilizes the pH of your soil.

This lack of organization leads to stress for you and your plants. Without a proper reservoir, you risk chlorine shock, temperature fluctuations, and the dreaded algae growth if you use transparent containers. Plus, the physical wear and tear of hauling water back and forth turns a relaxing hobby into a back-breaking chore.

The solution is simple: centralize your irrigation. With this square tank, you prepare your mix once, balance the pH, and you're set for days. Its opaque green material blocks light to stop algae dead in its tracks, while the square shape maximizes volume without wasting corner space in your room.

What it feels like to grow with a professional reservoir

Switching to a large capacity tank gives you an immediate sense of control. Physically, the tank feels bomb-proof; the polyethylene is thick and rigid, not flimsy like cheap alternatives. When you open the lid, you see a perfectly clean, oxygenated nutrient solution (if you add an air pump) ready to feed your crop. It turns the chaos of watering day into a simple "turn on the tap" or "switch on the pump" moment.

Emotionally, it’s a relief. You know that if you can't tend to your garden for a day or two, the water is there. It gives your setup a polished, industrial look that says "I know what I'm doing." Whether you are hand-watering or setting up automation, this tank is the silent partner that makes everything run smoother.

How to squeeze the experience to the max

To get the most out of your new tank and extend the life of your nutrient solution, follow these pro tips:

• Oxygenate the mix: Always install a small air stone and pump inside. This keeps the water fresh and prevents anaerobic bacteria from ruining your roots.
• Automate it: Connect a submersible pump to drip irrigation systems for total freedom.
• Elevate it: If you plan to use the included tap for gravity watering, place the tank on a sturdy stand or blocks (cinder blocks work great).
• Check the temperature: In winter, a water heater inside the tank ensures your plants don't get a cold shock.
• Clean between cycles: Scrub the interior with a mild hydrogen peroxide solution after every harvest to keep it sterile.
• Measure first: Before buying, check your door width! The 520L version is a beast and needs proper clearance.

Advantages and benefits in your day-to-day life

• Space Optimization: Unlike round barrels, the square shape fits perfectly in corners, giving you more volume in less floor space.
• Algae Protection: The opaque green polyethylene blocks UV light, preventing algae that steal nutrients and clog pipes.
• Durability: Made of high-resistance plastic, it withstands knocks, UV rays (suitable for outdoors), and the weight of the water without deforming.
• Versatility: Comes with a tap for manual use (great for filling a Watering Wand) and is easily drillable for custom grommets.
• Hygiene: The included lid keeps dust, pests, and light out, ensuring your water remains pure.

How it fits with other products in your set-up

This tank is the heart of your nutrition program. It is where you will mix your cannabis fertilizers to create the perfect cocktail for your ladies. Because of its large volume, it pairs perfectly with pH and EC controllers, allowing you to maintain stable parameters for days.

If you are running a hydroponic setup or a large soil grow, this tank connects seamlessly to standard irrigation piping. It's also robust enough to handle the vibration of powerful submersible pumps without rattling.

Frequently Asked Questions

Can I use this tank outdoors?

Yes, the high-resistance polyethylene is designed to withstand outdoor conditions and UV exposure, although keeping it in a shaded area helps maintain cooler water temperatures.

Does it come with pre-drilled holes?

The tank usually comes with a designated spot for the tap, but for other connections (like overflow or intake), the plastic is easy to drill with a standard hole saw to fit your specific setup.

What are the exact dimensions?

The 200L model measures 67x67x76 cm, the 300L is 77x62x83 cm, and the massive 520L is 119x77x84 cm. Always measure your access points before ordering!

How do I clean it?

Thanks to the large lid, you have easy access to the interior. Simply scrub it down with water and a little bleach or H2O2 between crops to keep it pristine.

Personal Experience of Pevgrow’s CEO (Alan)

I've used all kinds of reservoirs, from trash cans to flexible fabric tanks, but for a permanent indoor setup, nothing beats these rigid square tanks. I currently use the 300L version for my mother room. The best thing about it is the stability—I can lean on it while checking my plants and it doesn't budge.

One trick I learned: even if you don't use an automatic system, fill this tank and let the water sit for 24 hours before adding nutrients. It allows the chlorine to evaporate naturally and the temperature to stabilize with the room. Also, the tap at the bottom is a lifesaver for draining the last bit of water when you need to do a full clean-out. It's an investment that pays for itself in time saved.