Formerly Tidy Hydro | Established 2013

SMSCOM MK2 4.5A Twin Fan Speed Controller

SMSCOM MK2 4.5A Twin Fan Controller

Calculates the exact running speed to maintain temperature

  • Control your grow room temperatures
  • Avoid spikes in temperature
  • Controls intake and outtake fan at the same time
  • Easy to use, plug and play
  • Suitable for most grow room fans

It almost couldn’t be easier to use 

Simply plug your intake fan into the plug socket on the left and your extract into the right-hand socket and you are pretty much there!

Set the minimum fan speed with the left-hand knob to set the slowest speed you want the fans to run at, then use the right-hand knob to set the maximum fan speed.

Once the min and max speeds have been set, you just set the temperature threshold with the knob in the middle.

The unit calculates how fast to work and gradually adjusts the fan speed to react to the changing environment, helping to avoid spikes in temperatures.


Many growers opt to have their fans running on full power at all times but this can catch you out!.

The night time temperature has a massive impact on how a plant will grow. So if you have your ventilation system running during the lights out period in winter it could quickly get so cold that your plants are affected.

Purple stems are usually a good indicator of cold root zone temperatures from a cold night period.

Having your fans on a controller that keeps them ticking over on a low speed will usually avoid this problem entirely. 


The temperature of your grow room directly relates to how much (or little) your plant will be transpiring, and metabolising.

Unfortunately, these two things conflict with each other slightly. The higher the temperature the quicker your plant can metabolise, photosynthesise and make more energy to ultimately yield more flowers.

However, the hotter it is, the more the plant needs to cool itself. At a certain point the plant will not be able to adequately cool itself and will start to suffer as a result. Wilting, tip burn or leaf drop may all begin to occur, all leading to a bad finish.

Controlling the temperature to a point where the plants metabolism is nice and high, and it can still comfortably cool itself is the aim of the game when it comes to controlling your grow room environment. A fan speed controller makes the perfect choice when wanting to gain more control over your environment, in the day and night period.


The day time and the night time temperatures, should not really be looked at as separate entities. The difference between these two temperatures can induce different responses in the way your plant will grow.

The ability to manipulate the difference between these temperatures can give you more control over your plant throughout your entire grow.

A smaller temperature difference will promote the growth energy in your plant to go into vegetative growth. For example, 24 degrees C during the day and 24 degrees C during the night, is perfect for a mother/propagation room to encourage nice healthy vegetative growth.

A larger temperature difference will encourage your plants to put their energy into flower production. For example, a temperature of 28 degrees C in the day and 20 degrees C at night will encourage more flowering growth.

In the last week or so of flower, you can also use a larger than normal temperature drops to encourage a more colourful display in your flowers come harvest time. A wider range of colouring will usually be seen, but be careful not to go too low that plant metabolism is too badly affected.


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Delivery Information

We will dispatch your order as soon as possible and should normally be received within 3 to 5 working days in some cases please allow up to a maximum of 14 days. The delivery rate you pay is calculated on two things, the weight of your order and the postcode you enter. Currently we only deliver to the UK.

Delivery Rates
Weight Delivery Cost
0-5kg £3.50
5-20kg £7.50
20-30kg £15.00
30kg+ £50.00

Free shipping for orders over (Excluding bulky items) £150

Returns Policy and Procedures:

Your rights to return goods are protected under the EU distance selling directive. You are responsible for the cost and risk of damage when returning goods so postal insurance should be taken out to cover the value of the goods.

Unwanted Item(s).

If you have made a purchase form Tidy Horticulture you are entitled to cancel your order and return the goods within 7 working days for a full refund, including the cost of delivery. Notify us by telephone or email quoting the order number given and you will receive your refund within 30 days. Goods returned should be in a saleable condition and in their original packaging and with proof of purchase. Any unwanted items returned after this date will be at the discretion of management and any postage costs paid by us will be recovered.

Item(s) damaged in transit.

If your goods have been delivered by a courier and the item(s) or packaging are damaged then please sign for your delivery as ‘damaged’ and notify us by telephone or email within 48 hours. If the item(s) have been damaged in transit then you can return it to us within 30 days of receipt for a full refund or exchange.

Item(s) faulty.

If the goods delivered are faulty then you have a right to return them within 30 days. Make sure all warranty information is kept with your item. After 30 days you can also contact the manufacturer directly to enable them to rectify the problem for you. All goods must be returned in their original packaging for a full refund or exchange.


Tidy Horticulture
Unit 60 - 61
Faraday Mill Business Park
Faraday road
PL4 0st

Tel: 01752 225 225