Substrate heating...

George Farmer

Lifetime Members
Lifetime Member
Sep 6, 2006
Stamford, Lincs, UK
As a writer for Practical Fishkeeping magazine I don't recommend heater cables in my articles, or on the forums (as a mod on five now).

I've used them for a couple of years when I started, then not ever since. I noticed no difference. I even turned it off for 6 months during the two year period. No noticeable difference.

I won't use them again.

What do you think?

Please feel free to comment on the blog, or here, of course.

Practical Fishkeeping magazine | Blog: Do heater cables really work?

One comment from a fellow PFK contributor...

Yes, you can run an aquarium without them, and I did so for most of my life (had to!), but it is often a struggle, and unless you know exactly what you are doing, the risk of failure and wasted expenditure is high. A substrate cable at startup reduces the failure risk significantly for expert and beginner alike, and is absolutely essential for success in a soil-based tank.
:confused: :confused: :confused: :confused:

Tom Barr

Staff member
Jan 23, 2005
My blistering critique of heating cables is well known, as well as my experience and knowledge of them dating about to the late 1980's.

Unlike many, I've tested them, so has Claus, Ole and Troels. They are just as critical as me in person. They might be nicer on line about it. I am not:p

I've discussed the matter too many times on line over a decade and tested it beyond a reasonable doubt.

My approach is different, actually a better question should be asked than the marketing spam:

Show some evidence that heating cables helps plant growth in any way than say a heating pad or a good heater might? You need have the same temps in the tank for comparison.

At warmer temperatures, you get faster growth between 20C and 30C, this is a well known relationship in Biology called Q10, however, it has nothing to do with the method of heat nor circulation through a sediment, and anyone that's walked in lake or pond, river etc, knows the sediment is always cooler or the same temp as the water.

Heavier water sinks to the bottom, not warmer water, so it's not the least bit "natural", unless you want to defy the laws of density and physics.

The optimal rate of flow through a sediment for aquatic plant roots is about 0.5liters per m^2/day.

I challenge any heat cable proponent to show me a single test with good methods that can show a significant difference, any company for that matter as well.

This challenge has stood for over 10 years.
Heat cables sell for one reason, because of marketing, not because of science or that they actually work.

They are fine for heating the aquarium though:rolleyes:

Tom Barr

Tom Barr

Staff member
Jan 23, 2005
Or put simply,

The claims made by heating cable companies and the rsults given from their proponents do not support their conclusions.

1.Support of a conclusion is supported by:

2. Research citations(none have ever once been given in over 20 years BTW).

3.Repeatable well design methods that account for confounding issues such as CO2, nutrient variation, this has never been done by a single proponent to date that I am aware of nor do they ever know what you are talking about in general.

4. Aquatic plant growers do not use this method nor does Tropica which showed that the flow rates from no heat cables to be optimal and they actually can give you some real data, 0.49 liters m^2/day.
Ask any heating cable proponent how they might measure which parameter might be important and how they would go about doing this.

5. Organic matter content and loading rate. Never have any propoents ever once addressed this, yet these two things control all aspects of redox and O2 levels in the sediements.

6. Grain sediment size. 1 mm sand will have greater resistence to diffusion than 4mm sand, add some detritus and plant leaves, then things get really different.

7. No two tank's are the same, they imply using two works well for experimentation, this is a statistic of 1 for replication. Very bad likelyhood and confidence there. Best to use 10-20 tanks for each replication. Even to account for species and biomass differences, best to use split tank gravel beds, or cycle the cables on /off over several months to see.

8. New tank set ups are a poor judge to base their use. Simply using less soil, organic matter, or pre soaking it to leach the NH4 will resolve the issue, or perhaps a larger grain size gravel etc. With less soil added, there is less O2 demand in the sediment, the sediment can be 25 cm deep without any Organic matter and never become anaerobic, however and rich over loaded sediment 4 cm deep can become anaerobic and produce H2S. What controls this is the amount of organic matter, flow rate alone (which is rather hard for many aquarists to measure and clearly never done by the cable proponents) is hardly the defining factor, taken to an extreme, using RFUG's that can have their flow rates varied would/should produce the same result(*say redox levels*). Curiously, they do and for a price of 10$. These can be varied to a much greater extent than cables because the flow is direct.

9. Temperature influences growth, using warmer equal temps between treatments when making comparisons also helps rule things out. A Q10 between 20C and 30C increases metabolism rates by 2X for example.

10. There are no examples in natural systems. Sediments are the same or colder, colder water sinks to the bottom, not rises to the top.

Tom Barr

Tom Barr

Staff member
Jan 23, 2005
George Farmer;20180 said:
Thanks, Tom.

I'd have liked to see Walmsley read this, but even if he did, I doubt it would change his mind.

And you would be correct, however, you are not really interested in changing his mind. Honestly, are you at this point?

The way to do this and approach it as with most naysayers, is continued pounding for the truth, not at a personal level, as was the case with several arguments with Jeff.

Rather, the idea itself.
Attack that.

This does not matter if you hate the person or they are you best buddy.
You still go after it hard.

I listed several things above, the burden of proof is not on me, I already know and have tested and have examples to show that it does not help at any level to set up and maintain a planted tank to the highest levels as a scaper, a farmer/grow out, variety of species(I've grown well over 300 species) or just general ease and lower tech methods.

If I can do it without, virtually every single who's who of the aquascaping world can as well, I have intimate and professional academic and research background on this specific area, wetland sediments/soils, what are the odds, the likelyhood, that Jeff knows some secret the rest of us do not?

Now any person of reason viewing the debate can easily decide this one.
My pandering will not convince folks, they are the only ones that can change their own minds, not me. They do so of their own free will.
As with this approach, some folks will not, they can chose to ignore the facts and go with belief and perception. Not my crowd though:rolleyes:

I'm not out to convince someone who decides to make a conclusion, then goes about trying to find facts after. You observe, you ask a question, you try and falsify it(which every scaper and myself, as well as researchers and Tropica already have for decades), then use a treatments to see what results you get, then you interpret and discuss the results. Finally you try and make a conclusion.

The question I ask: does the data support their conclusions?
This is a basic question and critque we use in research and (peer)reviews of papers.

Nothing has shown this here. Nothing.
I hear the same old tired arguments put forth when Dupla marketed this back in the 1980's, not one new argument, not one new support, not one piece of research evidence has come forth since.

I can make the same Argument as Jeff or Dupla etc to sell diet pills, or Hydrilla virility organ enhancement pills:

RightFoods Hydrilla 60 Food Capsules

15$ for 60 little old pills, they are making out.

Also, ask Jeff how many heating cables he's made. I've made 4 in the past and recently 3 more.

You'll note, I do answer most every question and in full detail.
Of course I know the topic and have done my homework, Jeff's all talk and bully at that. Anyone that needs to use the law to bully someone in an argument is dirt in my book. Stay clear. Seems like he's the UK's version of Novak. Such behavior alienates the hobby and that person.

I'd rather stay here so not to incite another lawsuit threat rather than PFK or AE's site. Jeff is welcomed to try and use the law here to bully me in the USA.

You are welcomed to use what's been written above to most counter views.
However, Jeff's obviously got in for folks, so be careful, I'd not really even bother debating.

I'd just go about showing in separate debate and beat the living bejesus out of the logic and arguement.

Note: you and UKAPS are lot more people and a lot more vocal than one person and you have far more examples to prove him wrong.

Tom Barr