On Mar 24, 3:29 pm, "David Kershaw"
wrote:
Thanks Tom,
It looks like I have to back down ;o) Though I am still
a little unsure about slow growing plants from a low nutrient environment
being subjected to high levels of nitrate and having to compete with faster
growing species, I'm probably thinking more like a gardener than an
aquarist. I will concede the argument, potassium nitrate is a very different
animal to the nitrate resulting from the breakdown of ammonia. Thanks again
for taking time to explain.
Regards David

Well, think about this in terms of a reef person growing macro algae
in a refuge.
If you want to remove PO4 using the macro algae, why would you
severely limit NO3 as well?

The DBS needs a souce of NO3 to maintain a good rate of removal also,
and a carbon source like the macro algae leeching photsynthate.

Such concepts apply not only to FW, but Marine systems to some degree.
What occurs if you overstock the marine tank?
NH4= algae etc
NO3 to the same amounts N for N?
Macro algae growth.

Easy test.

Few will ever try or do it sadly.

Regards,
Tom Barr