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measuring hydroponic system temperature

6 Best Hydroponic Water Heaters

The best hydroponic water heaters answer one very specific need: heating up the water in our hydroponic systems.

Thus, it’s not a component that people with small hydroponic systems that are kept indoors in a properly warmed room might necessarily need. Although, heaters are also used by people with 5-10 gallon reservoirs, too.

If you have placed your bigger systems for growing plants hydroponically in a room that gets cold during the winter, that might mean that the water temperature in your containers drops considerably, which can impede the opportunity of growing plants when it’s getting very cold.

Not ensuring ideal hydroponic water temperatures can also lead to mold, mildew, diseases, low yields or loss of crops.

On the other hand, if the weather gets too hot, we’ll need hydroponics chillers, the complete opposite of heaters.

Heaters and chillers ensure that water temperatures are kept constant, in a range between 65-80 degrees F (18-26C).

6 Best Hydroponic Water Heaters for All Reservoirs

We need to look for the best hydroponic water heaters if we store our systems in areas that will negatively affect the temperatures of our water.

It’s one sure solution to ensure that we maintain an ideal temperature for our nutrient solution. It will ensure that plants’ capacity to absorb nutrients is maintained at optimal levels. And the roots will have high levels of dissolved oxygen available.

Hydroponic heaters keep our reservoirs at ideal temperature. Just like hydroponic water pumps, heaters are submersible devices that are placed inside the reservoir.

If the plants feel that the temperature is too low, it might lead them to think that the growing season is ending. That means that plants stop growing when water temperatures are too low, until temperatures warm again.

If you don’t want to get a hydroponics heater, you must ensure that you raise the temperature in other ways, like heating up the entire storage space. A higher air temperature is the simplest way to ensure that we get a higher water temperature but that might be quite costly for some of us.

Nevertheless, for big operations and serious growers, I recommend hydroponics heaters as the most reliable, effective, and easy-to-use option. It’s an investment.

1. Orlushy Submersible Aquarium Heater – One of the Best Hydroponic Water Heaters

I’m not saying that Orlushy is one of the best because it’s sold for pretty much the cheapest prices. Although, it’s really awesome that it’s sold for such affordable prices for all sizes.

Orlushy Submersible Aquarium Heater comes in the following sizes: 100W, 150W, 200W, 300W, and 500W.

Unlike most manufacturers that start at 50W or maybe even 25W for some, Orlushy starts off with 100W. I like it.

Plus, the 100W is suitable for 10 to 20 gallons reservoirs so it’s awesome for those with slightly smaller tanks.

The 500W works for 50 to 75 gallons. It’s a bit less powerful than some other 500W heaters. For example, the 500W heater from Vivosun warms up to 125 gallons of water. Thus, you must pay attention to these differences between manufacturers.

With the Orlushy Submersible Aquarium Heater we get precise temperature dial from 68 to 89 degrees F.

It’s made with thickened quartz glass. It’s supposed to be explosion proof and anti-cracking.

The reliable thermostat maintains uniform temperature and it automatically shuts off when the temperature is reached.

The buyers who have chosen the Orlushy Submersible Aquarium Heater for their hydroponic systems are extremely pleased with its performance, which is another reason for choosing it as a favorite of mine.

2. EcoPlus Titanium Heater

This is not an incredibly popular heater but I believe that it’s quite one of the best hydroponic water heaters.

There are people who absolutely love it. A buyer who bought it for hydroponics, mentioned in their review that it works great to regulate the temperature in hydroponic systems.

Another person mentions that, for the price, this heater can’t be beat. However, you should know that it’s not the cheapest you could buy but it has a really affordable price.

It’s a titanium heater and I like that a lot. When it comes to those made of glass, there are plenty of reviews from buyers that complain that theirs were delivered broken, the glass shattered. So we get to eliminate that worry because this EcoPlus is made of titanium.

The EcoPlus is ideal for both saltwater and freshwater.

The temperature range is 59 to 90 degrees F. It has a good range.

We get to choose from two sizes: 200W and 300W.

Get the 200W one if you have a 50 gallon reservoir and get the 300W if you have an up 75-80 gallon tank.

3. Cobalt Aquatics Neo-Therm Pro Aquarium Heater

This is one of the most expensive water heaters on the market. It’s about 2 times more expensive than the EcoPlus Titanium Heater for the same 200W size.

Cobalt Aquatics has a lot of sizes: 25W, 50W, 75W, 100W, 150W and 200W.

From what I saw, the 75W and 150W are not sizes we see often. The 75W can be used for up to 12 gallons and the 150W works for up to 40 gallons.

The electronic thermostat has a good range, from 68 to 94 degrees Fahrenheit.

Another nice feature is that the auto shut-off circuitry prevents overheating.

I also like that it’s made from shatterproof outer casing. The manufacturer claims that their devices are virtually indestructible.

Furthermore, we also get a LED display for both set temp and tank temp, simultaneously.

All in all, even if the Cobalt Aquatics Neo-Therm Pro Aquarium Heater is expensive, it also has interesting functional features that justify the much higher price.

But I also understand if you consider that it’s too expensive. After all, you might have paid half the price for your water pump.

4. Aqqa Aquarium Heater, 800W

We don’t often get to see hydroponic heaters of 800W and that’s why I wanted to review this one from Aqqa.

Besides the 800W size, they also have a 500W option.

The 800W heater is recommended for 80-220 gallons. That’s really big. But if you have a very big reservoir, you can also use 2 heaters placed on opposite ends.

A review for the 500W Aqqa, mentions that they have managed to keep the temperature at 89F in a 180 gallons tank with ease. That’s really impressive, although the 500W is recommended for 66-135 gallons.

The price is quite expensive for both sizes so let’s see what other features we get.

The shell of the Aqqa Aquarium Heater is made of PC plastic, which is very resistant.

The heating rod is made of explosion-proof and insulated quartz glass.

It has intelligent temperature control range 61 to 90 degrees F.

The heater powers off automatically when reaching the set temp. We are also shown the current temp.

It’s very easy to use and install.

5. Freesa Aquarium Submersible Betta Heater

This is one of the tiniest hydroponic heaters that one could buy.

Considering that you can buy a 25W water heater, I don’t think it can get any lower than that.

Most manufacturers actually start with 50W or 100W but Freesa is one of the few that offers the 25W option.

For example, I saw a review for someone who was using the 25W in a 3 gallon tank. That sounds about right. It works up to 5 gallons.

Thus, if you have a tiny hydroponic system, a tiny DWC or wicks, this Freesa Heater can be a nice choice.

There are also other sizes that Freesa offers, besides the 25W size: 50W, 100W and 300W.

However, while I appreciate the choices we get, there are plenty of negative reviews about the Freesa Aquarium Submersible Betta Heater so it’s not exactly my favorite among the best hydroponic water heaters.

6. Vivosun Submersible Aquarium Heater

Vivosun is a well-known brand in the world of hydroponics. They’re popular for grow tents, indoor hydroponic gardens, bigger hydroponic growing systems (NFT), grow lights, net pots, water pump, etc.

However, I’m not excited about their heater for systems and aquariums.

The thing is that buyers mention that it randomly stops working, that it breaks down after a few months or that it never shuts off. There are technical malfunctions that are really serious.

Thus, instead of recommending it, I’m actually warning you about the possible risks you can incur if you buy this Vivosun.

Of course, there are also plenty of positive reviews. One buyer names it the most recommended heater, mentioning that they have used one for over 1 year. Thus, it can work for very long periods of time, too. I guess it’s really a matter of luck if you get an awesome device or a faulty one.

For the Vivosun Submersible Aquarium Heater we can choose from an array of sizes: 50W, 100W, 200W, 300W, 400W, and 500W.

The 500W will work for warming up to 125 gallons of water.

Frankly, I’m impressed with this array of choices. And the price is cheap for all sizes so that’s another plus. I guess you should test it as soon as it’s delivered to make sure that it works properly.

How to pick the best hydroponic heaters

We need to choose our heaters based on the size of our reservoir.

The number of watts will be a clear indication of how powerful the device is. If we have a big water volume, we need more watts to get it heated up.

For example, a 200-250 watts heater will work well for heating up 50 gallons (190 liters) of water in a room temperature of 50 degrees F.

Of course, we could also couple two heaters if we have really big reservoirs. We can place a heater at each end of the tank, a setup that will keep the temperature consistent.

Another thing to keep in mind is that we should place our heater near the flow of the water. It ensures that the water it heats will circulate in the reservoir.

Best hydroponic water heaters: when we need them

When do you absolutely need to consider searching for the best hydroponic water heater?

If we were to look for the ideal water temperature in hydroponic systems, we would discover that, ideally, the water should have a temperature between 65 and 80 degrees Fahrenheit (18 to 26 degrees C).

This range is the one that will help us grow healthy roots and plants that have optional nutrient absorption. That happens because a water temperature range between 65 and 80 degrees F has high levels of dissolved oxygen at the root zone.

This range also encourages plant disease suppression.

Cold water causes plants to shut down and decreases their nutrients intake.

Those who grow in hydroponics will also notice that this water temperature is pretty much the room temperature range at which we are advised to grow our plants in our systems. Some plants will enjoy cooler temperatures, while others enjoy warmer room temperatures.

Thus, if the water temp drops below 65 degrees F, we might need a heater for hydroponics.

This article warns us that water temperature is critical in hydroponics.

Simply put, extreme water temperatures will diminish the plant’s capacity to absorb nutrients and water.

Since hydroponics means growing in water and nutrient solution with the roots supported by a growing medium, we absolutely need our plants to get the water and nutrients they need for a good yield. Without a good absorption capacity, there are no successful crops.

Most of us might pay more attention to choosing the best hydroponic nutrients or choosing the best hydroponic water pump but it seems that there might be situations where we need to look for the best hydroponic water heaters, too.

What if the water gets too hot?

Obviously, the focus of my reviews has been on talking about the best hydroponic water heaters.

But we can also have situations where the water gets too hot. Nowadays, we’re living through summers where record level temperatures are routinely broken. Those hot temperatures affect soil crops first. It’s always saddening to see crop failures, even if they’re not ours.

Moreover, extreme temperatures always pose a risk to our systems. I’m reminding you that the ideal hydroponic water temperature is between 65 and 80 degrees Fahrenheit (18 to 26 degrees C).

Hot water holds less oxygen so the roots of the plants will float on or be flooded with lower levels of dissolved oxygen.

When oxygen supply is insufficient, cellular functions in plants are compromised, which can eventually lead to death of the crop.

If the water gets too hot, we get a few solutions on hand:

  • painting our containers/reservoirs with white paint to reflect sunlight – this is one of the first things you should do if you live in hot climates
  • ice packs – instead of chilling our drinks, we can use ice packs to cool down the water in our hydroponics systems, however it can get quite time consuming if you get endless hot days and you have many reservoirs that need to be cooled down
  • cool water – adding cool water to warm water will cool it down but keep in mind that you will dilute your nutrients so make sure to top them off, too
  • hydroponics chillers – just as we have the best hydroponic water heaters to use during cold weather, we also have chillers to use in hot weather