cloudy water after use of Equilibrium

[crypticcrypt]

I have been using Equilibrium for many months now and have been plagued with a cloudy precipitate that develops after addition of the product. There is an intial cloudiness that disipates after an hour or so, but a fine sediment persists for many days. I've traced the sediment to use of Equilibrium after mixing and matching various product combinations.
It seems there may be a reaction with other chemical ferts that are being used but cannot really quite figure out what is going on.
I've placed finer sponges in the canister filter and this helps but still doesn't generate crystal clear water.
The other ferts that are being used are Potassium nitrate at 1/4 teaspoon per 20 gal and Potassium orthophosphate at 1/16 teaspoon per 20 gal. I can add the nitrate and phosphate without a reaction. Add in the Equilibrium and the precipitate clouds the water.

Any idea what is going on?

There is a laterite layer beneath the coarse gravel but I can't see how this would affect the situation as it is capped pretty well. The tank has been running well for 2.5 years.

The pH is 7.0, GH around 2-3, temp at 23 degrees (c). Kh around 1.0

This is not an over-feeding problem. The fish load in the 520L tank is light.

I was combining this with use of Excel for a few weeks but exclusion of Excel has made no difference to the problem.

Thanks

[Tech Support CH]

It sounds like you are causing a precipitation. The most likely culprit is calcium carbonate and magnesium carbonate. To test for this you can test your KH of your water and then add Equilibrium. If the KH drops you know that is the cause of the precipitation. To be on the safe side you may want to conduct this experiment separate from your aquarium. Another possibility is a calcium phosphate or magnesium phosphate. These can occur when you have high phosphate levels. What level are you running your phosphate at? And also try to dose the potassium orthophosphate on a separate day than the Equilibrium.