I will be adding 6 air stones to the grow beds 3 in each. plus I have two air stones int he fish tank so plenty of DO. Also as we know the pH goes down over a period of time because of the fish growth and food consumption. The answer here is simple. We have very hard water here with a pH between 7.2-9.0 depending on the season (rainy or dry). Adding some hard water to this system is easy.

I am not sure but I had poor growth with gravel plus after only 1 1/2 years I had to clean the gravel. with Gravel I had lower Nitrate level, low Nirite level, low ammonia but it kept the pH higher. Until we can get a grip on the gravel here I will do a float bed.

With the filters I made I have to clean the pre-filter twice a week and the post filter once a week. I have no solid waste going into the system at all. I am hoping that once we get the larger system set up. we will have a grammarus population established and even some prawns in the float beds.

My chemical levels of the current system are at the preferred levels that Susanne Friend and Tim Mann suggest for a Organic float bed system. I hope to have are operating fully organic as theirs which includes scuds, shrimp. Tilapia. When Grammarus scuds are established their shed exoskeletons it naturally add calcium to the water which counter balances the pH to 7.0.

This heterotrophic bacteria you are adding to your system. Is that naturally found in nature as a way to control food waste from the fish? or is it something like yeast which creates a bacteria that break down the solids. How does it affect your system chemistry?

At the moment my fish are doing fine and are growing (fattening) they are eating around the same amounts as before only a slight increase of food so far. They are growing. The gold fish died from territorial attacks by the Tilapia. You could see that their fins were bitten even their faces were bitten. When I had only a few Tilapia and mainly Goldies the Goldies were aggressive toward the tilapia. but once my Tilapia population increased and they out numbered the Goldies 2 to 1 that is when they became the victims. during that time the Ammonia levels as they were most of the time with gravel so low they didn't even measure in my test. So far this last three weeks the ammonia level is stable at 0.25. Nitrate at 0.70, Nitrite at 0.50, and the pH fluctuates from 6.6-7 currently today it is 6.8 because I added high pH to the water to balance it.

thanks for your articles by the way. I have found them interesting and I have cut and pasted them into Word Doc for additional reading for our ex-con trainees.

Do you like my new avatar? That is my little mermaid of 14 years. Actually she very rarely gets in the water and that pic is 19 years old now. She hasn't changed much since then. a little gain from having children but still that big beautiful smile. My youngest daughter has the same smile.