Sunday, August 25, 2013

We had seen ponds that had whitish foam around the waterfalls and around some of the rocks near by. The bubbles that this foam made took a long time to pop, what is that foam from? Is it bad for the fish in our ponds?


Q:
My wife and I went on the pond tour; we had seen ponds that had whitish foam around the waterfalls and around some of the rocks nearby. The bubbles that this foam made took a long time to pop, what is that foam from? Is it bad for the fish in our ponds?


A:
The foam is a mixture of oils, proteins, fats, and other organic compounds that accumulate in the pond water. Some of the foam will derive from your fish and from the decay of uneaten fish food and some comes from the breakdown of plant debris and algae.

The foam commonly found around the base of waterfalls, with the physical actions of churning water causes the substances to break out of the water column and coalesce as foam. If the majority of compounds that comprise the foam come from plant decay, and/or plant matter, the problem is unattractive but not that harmful to the fish. However, when the majority of the compounds originate from fish sources, it can become very hazardous to the animals in any aquatic system.

Studies have shown that fish kept in water polluted with fish-derived dissolved organic compounds suffer a higher rate of disease and parasitic infestations and do not grow as sound as fish kept in water with substantially lower concentrations of the substances. The concentration of these substances will also lower the redox potential of the pond waters and substantially decreases the ability for the water to carry oxygen.

Because there is no easy way to tell, whether the foam in a pond is fish-based or plant-based. The higher the fish load in the water body proper, the greater the likelihood that the substances will be fish-based, and are a potential cause of fish disease problems.

This is why some of the higher tech ponds will install a foam fractionator, which will remove the dissolved organic compounds from the water. Ozone may also be used as a supplement to the foam fractionator to help remove the organic pounds.

A normal molecule of oxygen (O2) has two atoms, and ozone (O3) has one additional atom. The extra atom is highly unstable and is an intense oxidizing agent. The main reason for its uses is to eliminate unwanted dissolve organic products by increasing the systems redox potential and applies to a sequence of chemical events in which elements and compounds transfer and/or rearrange positive and negative electrons. Elements and compounds that want to gain an electron are “reduction agents” and have a negative charge. Those that want to give up an electron are “oxidizing agents” and have a positive charge. Measuring the effectiveness of this process by its minute electrical charge it generates in millivolts (mV) with an Oxidation Reduction Potential meter (aka: ORP meter). We must also remember the effluent from an ozone contact chamber must be passed over a bed of activated carbon to remove residual ozone before it returns to the pond. Even though residue ozone is short live, usually less than an hour, the residue can damage fish tissues and other inhabitants of the pond plus reduce its natural fauna.

In addition, ozone does not add dissolve oxygen in the pond water, at least in any significant quantities that would benefit any of the pond inhabitants. Depending upon your pond husbandry practices, it is very possible to get by without it. However, before any hobbyists turns to its use, increasing dissolve oxygen in the pond by increasing water circulation, reducing bio-load, trying a more efficient and/or better designed filtration system, and increasing the ponds general maintenance level, seems to be preferred over ozone usage.

A disadvantage of the foam fractionators (aka: Proteins Skimmers) is that some beneficial organic and inorganic trace elements are also removed. So systems with efficient protein foam fractionators must be monitored for loss of these elements. This skimming process does not work as well in freshwater, due to the almost neutral pH, and this reduces the electrical interaction between organic molecules and water, which decreases foam fractionation. In addition, the lower density of freshwater reduces the formation and stability of tiny air bubbles (the addition of salt may be needed). The only time foam fractionation and ozone is to be used, is when the stability of the pond is in question.

A fractionator can be very beneficial to the pond, but it does not fit within the modus operandi of every pond enthusiast. It has to be cleaned, adjusted, and cared for on a daily or weekly basis, or else it will become useless.
Two different sizes of Clarity Protein Skimmers for pond use; not only are they big but also must be hidden from view somehow from onlookers. They are only necessary for those that have high organic waste from dead plants, over feeding, too many animals in ones pond, inadequate filtration and bad husbandry.  These two expensive protein skimmers will help cover-up ones mistakes but they will not correct what is wrong in the first place and are only a Band-Aid in pounding…not the cure!
Photo taken from Internet.







As I wrote this I decided to run outside and take a photo of my ponds waterfall -above two photos- to see if there was any protein bubbles…nope! That’s why my TDS, CE and Redox are so high in my pond because with proper husbandry and with the Anoxic filter I don’t have to worry about organic waste buildup. 


Anoxic Filtration System ®
February 02-2005-2013
New Updated Version

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