Black Brush and green algae problems.

I recently redid my substrate last may and replaced it with the Black
Oceanic substrate. It looks great and haven't had many problems. I tried to
remove any Malaysian trumpet snail eggs from the plants. Now the snails are
back, quite a few. Usually 2 every inch of substrate. I have noticed within
the last month, black brush growing again and a green film on top of the
water. I do biweekly water changes now, aprox 30%. I did notice that the
nitrates are about 12.5, I added some nitrate remover today as well as added
co2 again at 2 bubbles per sec. Nitrites are ok, ph, 6.8, no phosphates, no
ammonia, GH 7 KH are about 3.

Is it possible that the amount of trumpet snails could be effecting the
nitrates? The fish are fine, japonica are well, and everyone is happy,
except me since the algae is becoming a real problem.

Any suggestions on how to remove them without chemicals?

Thanks.

--
Later.

D.E.

Have a better one.

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