Hi all,
And then let's consider aquasoil. This stuff and others , releases vast amounts of ammonia ( off the scale last time I used it)
Much more ammonia than I cycle with (2ppm) So what's it gonna be chaps?
You can't denounce cycling with ammonia
When many of the most expensive and fully loaded substrates release much more ....
Curious...
I've never used any of the complete substrates like "Aquasoil", but if you have a high nitrogen environment (particularly with high ammonia) the answer is just to increase the plant mass (and particularly plants with access to aerial CO2) and add extra aeration. You can then use the colour and growth rate of the floating and emergent plants to give you an approximation of the nitrogen content of the water.
This is the original "
Duckweed Index", where is was developed for high nutrient situations. The great advantage of a large plant mass is that you have a negative feedback loop <
"Growing Duckweed to Recover Nutrients from Wastewaters and for Production of Fuel Ethanol and Animal Feed">, where increased nutrients drive increased plant growth, and increased plant growth depletes the available nutrients.
There is more in these threads on UKAPS <
"bacterial colony or algae?"> & <
"N2, harmful or not?">.
The real difference between plant/microbe systems and microbe only systems, like an un-planted tank without a substrate, (or with regularly vacuumed gravel) and a filter is that the maximum potential capacity of the "microbial only" system is only about 10% of the plant/microbe option.
Theoretically you can improve nutrient removal in microbe only systems by adding anaerobic denitrification in a plenum or deep sand bed. This is possible, but has a number of practical disadvantages. <
"Alfagrog for reducing nitrates">
The same applies to building up your microbial denitrifiers by adding ammonia (either via direct ammonia/urea addition, or by heavy stocking with fish). You can do this successfully by adding "Amquel" or "Prime", where the NH3 is combined into non-toxic compounds, or by frequent water changes - "
the solution to pollution is dilution", or by waiting for the microbial biomass to complete "the cycle".
It isn't that these methods don't work, they just introduce additional risks, mainly because ammonia is a toxic compound, even at low concentrations. We can't see the filter bacteria, and it is difficult to accurately measure the ammonia in solution with the test kits available to us, but we can see plants, how green they are, and quickly they are growing.
Plants are an obvious visual indication of nutrient status, it's a KISS solution.
cheers Darrel