Advice needed from cheato reactor experts

[Muffin87]

The instructions for my Tunze chaeto reactor (large version) say:

Algae must be harvested every 3 to 4 weeks - depending on growth. Maximum production: about 350 g (12.3 oz.) per month. Refill the with about 40 g (1.36 oz)

Two questions:

1. I don't really understand how the reactor can keep the nutrients stable, if I get rid of 90% of the cheato. Should I really toss about 90% of the cheato when I harvest?
2. I measured out 390 grams and it's not really that much cheato. At the moment I have about 600 grams of cheato in the reactor, and without water, it fills only half the reactor.

Any tips on the "how much cheato" question will be greatly appreciated.

Thanks!

 

[Formulator]

The chaeto uses your nutrients to grow, so as long as it is actively growing, you are removing nitrate and phosphate from the water and “locking” it into the chaeto. So then you remove the chaeto so it has more room to grow. You need to imagine nutrients being converted into new algae, rather than thinking of it as a stable clump of algae eating up the nutrients where logically more algae would eat more nutrients. Hopefully that makes sense. So yes, remove 90% to give it more room to grow and continue converting nutrients into new algae.