I would definitely only dose one trace element program at a time. By using marine trace elements all in one and Red Sea color program you’re adding too much and could end up with nutrient issues. The iron test can be confusing. Here’s what Red Sea says about in the FAQ section of the test kits.
I have tested for Iron using the Colors test kit but I always get a zero reading, is my test kit faulty?
No, your test kit is not faulty.
The iron cycle is a very complex in the marine environment and it can be found in many chemicals forms, from free ions through inorganic and organic molecules up to large colloids connected to metals. This “soup” of chemicals increases the probability of spontaneous reactions, causing elements to spontaneously switch between phases.
These changes are enhanced and controlled by many factors such as salinity, pH but mostly by changes in alkalinity and the amount of organics and colloids in the water.
In a closed system such as an aquarium where there is often a high organic load and many dissolved organic colloids, the amount of free iron could be very small although the total iron could be very high. Usually this situation will lead to a darkening of the corals due to growth in the zooxanthellae population, and an outbreak of phytoplankton and other macro algae, even though you may measure zero levels of iron. On the other hand, in very pure saltwater most iron will be present as free-iron ions which can be toxic.
After a few minutes from the time you add the iron (Coral Colors C) to the aquarium you will probably measure levels around 0.05 ppm. This may last for several hours before it drops to zero (usually within 24 hrs). The reason for this is that the iron may have precipitated or bonded to organics substances.
The use of the Iron Test within Red Sea’s Coral Colors Test Kit will ensure that Iron is not over- dosed as long as the iron is still in free form. However the test will not detect iron which is not in its free form, and therefore a zero reading should be treated carefully as any overdose will cause stress to corals.
