How to use an aquarium heater for regulating E-6 and C-41 temperatures.

A few weeks ago I finished a roll of slide film from the fall/winter and shot 2 more of some images we are using for a lost soul deck. I took these rolls to Dan’s Camera City to get developed, but I got a call later that night saying that they no longer do it on the premises and to have it sent away would cost $16 a roll, plus $5 for every one stop I wanted each roll pushed. Since I pushed my velvia to 200 that would have been a huge amount of money and it would have taken like a month to get back.

It turns out the slide chemicals were a fraction of that price (I think $20 from freestyle photo), but I wanted a way to keep the chemicals a constant temperature since I had a tough time keeping my c-41 chemicals the right temperature in my sink, and it was always a nightmare when I was doing multiple rolls at once. The negatives all came out usable, but I demand excellence since this was my first time developing slide film and I was intimidated.

After some research and reading through a lot of photography forum threads from at least 5 years ago I learned that instead of investing in a novatronic heater or something expensive it’s possible to use an aquarium heater as long as it is the type of heater that can be cranked above the recommended temperature. These companies don’t want to be responsible for fires or boiling your fish alive, but there are some cheap ones that are easy to “modify”.

The heater that came up a few times was the Tetra submersible heater available from Wal Mart, and the best part is that to “modify” the heater to keep a constant 102 degrees F doesn’t require any hacking or soldering. All I did was crank the knob up to it’s max setting, pop the knob off, put the knob back on set to the middle of the dial and crank it up a little higher.

Admittedly, it takes a bit of fiddling to get the temperature right. Without an LED display like a professional dark room heater it takes a lot of patience to get the knob set in the right position. It took me a few hours of adjusting to get an acceptable temperature, but once I had it right it held the temperature long enough for me to develop 3 rolls of slide film. I would bet that I could have done 3 more without any change in the temperature. For my rolls of E-6 I had the heater set at 102 degrees (not recommended but I wanted to set it for C-41 also), but this heater is definitely capable of doing 105+.

Hopefully this helps anyone who stumbles upon this post. With businesses that develop film in house becoming more and more rare I can see a lot of people interested in their own developing set ups. I hope this post encourages you! It’s intimidating but just as easy (if not easier) as developing black and white.

P.S: The heater I used was the “Tetra Submersible Heater for 30-60 gallon aquariums” bought from a Wal Mart. I made sure it was the right type in the store by opening the box and seeing if the knob could pop off. You should also get a little pump to keep a constant flow so the temperature is evenly divided.

P.P.S: I am not responsible from houses being burnt down, electric shocks, or fish being boiled alive. Do this at your own risk! Obviously it’s not a great idea to mess with any appliances especially ones involving electricity, water, and heating elements. Just be careful, use your head, and make sure your smoke detector has working batteries.

P.S.P.S: The glass on these heaters can break if you take it from one extreme temperature to another, so make sure to gradually change temperatures and leave the heater unplugged in the water after use so that it cools slowly. Send me an email if anyone finds a cheap metal heater that can be modified.

Mixing the chemicals. The Arista pint kit is easy to mix because it comes in liquid form, although you’re gonna definitely need access to some hot water to mix the blix (140 degrees F). I also mixed my new Unicolor C-41 kit that night too just to get it over with and powder is such a hassle compared to liquid.

My set up.

A few days later I upgraded to a cooler to help keep the water at a stable temperature. All in all I probably spent as much as getting those 3 rolls developed, but now I have a good set up and never have to pay someone to do what I can easily do myself!

Everybody N 2 Gether Now.

Now for the results:

Out of focus and nothing too colorful going on here. I still like it, but not a good use for slide film I guess.

This one looks even better in real life!

I have more I want to show off.. but they’re all secret at this point.

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