My diatoms are back. I replaced the material in my phosphate reactor
which knocked them back for a few days, but they rebounded again. My
nitrates and phosphates are both undetectable.

I'm thinking this is silicates although I'm still waiting the arrival of
my test kit. I thought my RO/DI unit would take care of this, but I
also heard that it only works on silicates for the first 100 gallons.
Is there a better DI media for this?

I'm doing 10 hours of lighting and I haven't changed this for a long
time. I'd hate to change it because my ritteri is finally looking good
after nearly 6 months of nursing it back to health.

Any ideas?

--Kurt