What is Rowaphos?
RowaPhos is a unique man made ferric hydroxide material specifically produced for efficient removal of phosphates, arsenic and silicates from fresh and salt water, having initially been developed in
Germany for treating mains water supplies. As such it should not be confused with natural materials, which are generally based on aluminium oxide, (zeolite).

RowaPhos is manufactured using a Patented process which makes it physically and chemically completely different to the vast array of other iron based media which have sprung up to ride on the sucess of the Rowa product. Most of these products are iron oxide based and have a higher capacity for phosphate than aluminium based medias but do not touch the engineered properties of RowaPhos.

In an independent series of tests carried out by the Berlin Technical University on the five most commonly used phosphate removers at the time, RowaPhos was found to be the most efficient in removing phosphate from water. Other medias tested reached only to 30 – 40 % of its removal capacity by weight. Additionally RowaPhos was found to continue to remove phosphates at lower concentrations and had a higher maximum holding capacity.

Why the article?
In regular conversations with hobbyists around the world it has become obvious that many people currently using Rowaphos have no real concept as to its correct use within the aquarium and use it like ‘magic pixie dust’ on its reputation alone. They have it a small pouch of media in the corner of their tank or sump and have no idea how it works or even what their phosphate level currently is. I know that this is true as I was such an individual once.

What are phosphates?
Phosphates are naturally occurring inorganic salts, which are found in all living things. They can therefore be introduced into the aquarium from a wide range of sources such as; from fresh water supplies for those not using R.O. water; from decomposition of uneaten food or fish waste; from death of plants and animals in the tank; from impure aquarium chemicals such as cheap activated carbon: or by slow release of absorbed concentrations from rocks and tank substrates.

What is the effect of phosphate concentrations on my tank?
Within the reef aquarium, phosphates will greatly affect the formation of hard coral skeletons by reducing calcification by over 50% and by inhibiting the deposition of strontium. It is suggested by Borneman that phosphates are a direct poison to calcification.

For other aquarists with fresh or salt water tanks the main drive behind the purchase of Rowaphos is to control the growth of nuisance algae within their aquariums, which can in some cases overrun plants and expensive corals spoiling the aesthetics of the tank and in extreme cases killing its inhabitants.

Phosphates are food for nuisance algae along with other nutrition such as nitrates and light. The problem often becomes worse or apparent when changing to more intense lighting such as to HQI or T5 units.

Tullock states that there is no simple way of controlling excess algae, as there are a number of factors involved, however in most aquarium situations the limiting nutrient ion in terms of algae growth is phosphate.