<a href=showthread.php?s=&postid=14468993#post14468993 target=_blank>Originally posted</a> by ChrisMc73
These are all benefits of CHEATO?
Indeed. Chaeto utilizes phosphate (PO4) in it's cellular structure, allowing it to grow; it obtains this P04 by absorbing the ions dissolved in your saltwater. When you prune/remove the excess chaeto from the fuge as it grows, you are effectively removing PO4 from your system since it is bound within the algae's structure. On a side note, that is why algae blooms in the ocean occur when fertizlizer (a main component of which is P04) is allowed to runoff or dumped straight into the ocean. This in turn clouds the water, suppressing sunlight penetration and thus limiting/stopping the growth of photosynthetic organisms growing at depth in a given body of water.
On the topic of growth, it is important that you prune your chaeto regularly because if it is crammed in there it will stop growing, which halts phosphate removal because it is not using it to grow. Also on the topic of growth, plants use photosynthesis to produce energy and/or grow. Photosynthesis is a chemical reaction combining light and carbon dioxide (C02) within chlorplasts to produce simple sugars. The pH balance of our tanks is on a daily cycle. This can mostly be attributed to photosynthesis. During the "day" when the lights are on, photosynthesis is taking place and algae, be it macro or micro, is absorbing dissolved CO2 from the saltwater. CO2 is produced by things like fish respiration. Now, the ion that they are absorbing is carbonate which is by nature an acid. Ph is a measure of how acidic or basic a solution is based on the amount of hydrogen ions floating around in solution. Anyway, long story short when photosynthesis is taking place during the day there are less carbonate ions floating around which makes the pH higher (more basic). At night, when photosynthesis has stopped, pH begins to fall (i.e. become more acidic) because there is more dissolved carbon dioxide in the water since there again, no photosynthesis is taking place. Running your fuge lights on a reverse cycle alleviates this issue, not really sure it's a problem, to an extent because it allows photosynthesis to take place all day, in your display tank during the day and in your fuge at night.
To the last point, it is a refuge for pods because there are no predators to eat them in there. They eat algae, multiply, and find their way back into your DT when they're blasted out your return pump or poured back in after giving your pruned chaeto wad a good shake.
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