In many fish only systems, keeping algae will allow the aquarist to almost eliminate the need for water changes altogether. Also, many aquarists don't know it but macro algae actually use all of the toxins that we must watch so carefully in our aquariums. Ammonia, nitrites, nitrates and phosphates are used by algae as fertilizer and are removed from the water to make for happier fish.Simply float the unopened bag containing your new algae in the tank for about 30 minutes to 1 hour to allow the temperatures to match up. Then place the algae in your tank. Caulerpa Peltata will attach itself to rocks or substrate.).