Lakes & Ponds

Algae and bacteria require trace quantities of phosphate to grow.  A heavy bloom of algae can be very serious for the lake and could result in mass mortalities among the fish and make the lake look unsightly.  Phosphates also promote the growth of cyanobacteria or blue-green algae which are not only unsightly but they are very poisonous. If a lake experiences a blue green algal bloom then humans as well as animals must not be permitted near the lake.

DrydenAqua manufacture NoPhos  and have been using it to control phosphate and algae levels in public aquaria, water parks and lakes for many years.  The product is non toxic, so it doesn't control by killing the algae. Instead NoPhos reduces the amount of food or fertiliser and so slows down the growth of the algae. Since bacteria also require phosphate, NoPhos can slow down, stop or prevent bacterial growth.

Application rate.

1. If there are no fish or aquatic life in the lake, then you can bulk dose NoPhos to a high level, at a high concentration you prevent any phosphate release and provide almost crystal clear water, even with no water filtration.

2. ACP can also be used, ACO acts as a catalyst using the power of the sun to disinfect water, for more information on ACP click here.

3. If there are fish, or plants in the lake,  if you completely remove the phosphate then the fish and plants will not survive. Under these conditions you should aim to reduce the soluble phosphate (ortho-phosphtae) to approx 0.1mg/l as PO4-P
 

Calculations

NoPhos + PO4^-3 = NoPhos PO4 (s)

1kg of NoPhos will remove approximately 100g of Phosphate as PO4 -P

1kg of NoPhos will remove approximately 300g of Phosphate as PO4

Example.

Volume of water in the lake = 20,000 cubic meters

Concentration of phosphate as PO4-P = 0.5 mg/l

Mass of phosphate = 10,000g = 10 kg

Amount of NoPhos required = 100 kg to remove all of the phosphate

Once all of the phosphate has been removed, the NoPhos application rate will depend upon the phosphate input to the system. Normally the quantity is very low, but it should be monitored to make sure that you maintain zero phosphate in a sterile  lake, or below 0.1mg/l in a biological lake.  We have portable water test kits available that can measure down to 100ppb of phosphate.