*Free Delivery on all orders over £20 - available for a limited time only, order today and save £££s - Secure payments, discreet packaging!

Incredible Street Light LED offer live now instore only! - Dont miss out!

For a limited time you can buy the yield busting Street light 680w LED for just £575.00 when you pay digitally instore!

In fact come and see us for incredible discounts on all our LEDs including the Maxibright Daylight range and the mind blowing new 2.9umol Lumatek Zeus 600w LED!!

View all our LEDS now!

FloraFlex Rockwool Drip Components

We're please to stock the FloraFlex range of drip irrigation products including FloraCaps, Stackers and the FloraClip drip line clips. Check them out today and help evenly distribute your nutrient supply whilst beating the dreaded algae problems associated with rockwool growing.

FloraFlex Rockwool Drip Components

The Best LED Lighting Available - Huge Stocks

View all LED Grow Lights
Maxibright Daylight 660w pro LEDMaxibright Daylight 660w pro LED
Maxibright Maxibright Daylight 660w pro LED
Sale price£779.95
In stock
Dio-Tech 830w LEDDio-Tech 830w LED
ControLED Dio-Tech 830w LED
Sale priceFrom £189.95
In stock
Sun King LED 630w - 2.7umolSun King LED 630w - 2.7umol
Not specified Sun King LED 630w - 2.7umol
Sale price£624.95
In stock
Maxibright Daylight 1030w Pro LEDMaxibright Daylight 1030w Pro LED
Maxibright Maxibright Daylight 1030w Pro LED
Sale price£1,349.95
In stock, 5 units
Infrared Thermometer
Not specified Infrared Thermometer
Sale price£29.95
In stock, 11 units
Maxibright Daylight iLink Cable
Maxibright Maxibright Daylight iLink Cable
Sale price£12.50
In stock
Lumatek Zeus 1000w Xtreme PPFD LEDLumatek Zeus 1000w Xtreme PPFD LED
Lumatek Lumatek Zeus 1000w Xtreme PPFD LED
Sale price£1,549.95
Re-stocking soon
Daylight LED 480w ProDaylight LED 480w Pro
Maxibright Daylight LED 480w Pro
Sale price£749.95
In stock

NEW!!! - Introducing the Grodan 'Big Mama' rockwool blocks

After waiting many years for these huge rockwool blocks we can finally announce they are here and available now! Hugely popular in the USA these blocks are ideal for growing plants to full maturity check them out today.

Get 'Big Mamas' today!

Lowest priced 630w LED tent kit just £749.95!!! - get yours today!

FOR LESS THAN £750 YOU CAN GET- 2.7umol 600w led tent kit with professional light hangers (not cheap chain and hooks) and for a limited time a free nutrient starter kit included! WhispAir extraction system and heavy duty timer included!

Sun King 630w LED tent kit

Find us....

Critical Mass Systems Sheffield

Unit 4, Holbrook Enterprise Park,


S20 3GL

Monday, Tuesday, Wednesday & Friday: 9AM - 6PM

Thursday 9AM - 7PM (Late Night)
Saturday: 10AM - 5PM
Sunday: 11AM - 4PM

Get directions