The Cyclops-7F blue excitation version may be best for your needs if you are working in high turbid water conditions, but it is affected by CDOM. Alternatively, Cyclops-7F red excitation is able to ignore CDOM completely but will be affected by high turbid conditions. If you are able to prioritize which of these problems would be in your water system, one or the other would work. Otherwise, if your area has both turbidity and CDOM issues, both sensors could be used in tandem since they can see the same concentration of chlorophyll. You would just need to create some offsets of the variation between the two.

In terms of reading CDOM and correlating it to Chlorophyll a, Cyclops-7F blue excitation would act like a CDOM sensor in the presence of CDOM since it can respond linearly. If instead you would like a CDOM and blue excitation sensor to work together, all you would need to do is create an offset since both datasets would be linear.
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Cyclops-7F Red excitation works best in the bay and freshwater. The sensitivity of 0.3 ug/L is responsive enough to the algal species typically found in those water systems. It would be worse suited for the ocean environment since the Minimum detection limit is so high. It does not see CDOM at all, just chlorophyll. Which won’t really be a factor in the ocean since CDOM and cyanobacteria are not found in high abundance in that water system. Cyclops-7F Blue excitation is great for the ocean. It has a low minimum detection limit at 0.03 ug/L and you will find for that reason it operates best in ocean environments. It can reject turbidity a lot better than red, but not by much. This is entirely due to the way the instrument is built and the wavelength it operates at.
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Clean the Cyclops-7F as often as you like, use clean tap water or deionized water to rinse off the sensors. It all depends on how long it is out in the field and the conditions present in the water system. See what works for your needs. If there is something like a barnacle growing on it, use soap and water. If you have to use an abrasive, I suggest the yellow side of a Brillo pad like sponge, not the rough green side or a soft bristle toothbrush.
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The Cyclops-7F resolution would be a 12 bit ADC logger. It wasn’t meant for highly analytical work or detailed data logging events or high-resolution studies. If we did mean for it to do any of those things, we wouldn’t configure it for 12 bit, it would be a 24 bit logger.

As the autogain on the Cyclops-7F increases, the sensitivity increases and the concentration range decreases. Our optical specification guide available on our website also lists the limits at which they can read at, example: linear range of 0-1000 ppb for Rhodamine. Keep in mind that this gain switching does take seconds to readjust.

The minimum detection for both sensors, C-Fluor or Cyclops-7, are the same. There is no change in accuracy from one probe to the other.

The Cyclops-7F and C-FLUOR have the same optical configuration so the interferences from iron would be similar, but not the same. This is something the customer must determine for their water system. I can say that very high turbidity and Fe concentrations will interfere with almost any optical measurement simply due to light blocking interactions, but I can’t say to what degree.

Cyclops-7F can only perform to the minimum 1 reading/second, and C-FLUORs can perform 1 reading/half a second. In terms of why this limitation exists, it was not designed for faster or slower readings, just for 1 reading per second or 1 Hz readings only.
These units are for use in water and in environmental conditions, many individuals who use our products aren’t looking for utilities of sub seconds readings mainly since it is for monitoring purposes. It is highly likely that the environmental conditions will affect the readings, but it should not differ greatly between seconds.

While the sensor may have an increased signal when reading chlorophyll in leaves, its intended purpose is to be in vivo or applications with submersion in a liquid.