Reprinted with permission fromKOI USA Magazine
Recently, Barbara and I discovered the intrigue of fancy goldfish. Although our primary interest still remains with Nishikigoi, there is, nonetheless, a certain appeal inherent within the varieties offered by quality goldfish. All Koi basically look alike if body shape and finnage is considered. Such is not the case with goldfish; this factor has led to developing interest on our part. However, the subject of goldfish is not the intent of this article even though I suspect that there are many Koi fanciers who also share an appreciation for Carassius auratus.
As a result of this interest we undertook the construction of a small (105 gal.) pond within an enclosed garden area. The pond was dug and concreted with this writer accomplishing the labor. After building the pond over a network of wire mesh, a 1/4 inch layer of mortar cement was applied to smooth and seal the surface. Since I was concerned with leakage, a layer of Thoroseal was then added as a final coat. This was a mistake for a very rough surface ensues when using this product. Upon filling the pond we experienced six days of wild pH fluctuations which I suspect was attributed to the Thoroseal itself or that it was not sealing against an alkali leach from underlying mortar. In an effort to stabilize pH, muriatic acid was added daily but to no avail. Finally the pond was pumped dry and the Thoroseal heavily scraped to again smooth the surface. White vinegar at full strength was brush-scrubbed over the pond on two occasions and the pond was refilled. Still the pH bounced all over the lot. What to do?
Sometime ago, in a conversation with Mark George of Golden Pond, he related there was a rubber product which could be brushed over fresh concrete to seal from leakage and to also prevent an alkali leach. Recalling this, I phoned Neoprene Rubber Company in Jacksonville, Florida. Following a conversation with Mr. Larry Hecht, Vice-President, I purchased a gallon of their Neoprene black rubber paint. This was applied by brush in three separate coats to the new pond and the results were amazing. This is a fast drying product requiring only 45-60 minutes between coats. Once the final coat is applied the rubber should be allowed to cure for at least 24 hours. Not realizing this, I filled the pond after a two hour cure and introduced an ordinary Comet as a test fish. Within a short time this fish exhibited all the signs of being badly stressed and I removed the "victim" suspecting water toxicity from an incomplete aging period for the rubber. The pond was again emptied. After a 36 hour curing period, the pond was refilled and the same fish was reintroduced with absolutely no ill effects. Frequent monitoring of pH revealed no fluctuation whatsoever and, two days later, our collection of fancy fish which had been placed in a "holding pattern" in the top of our Koi biofilter were introduced to the new pond. It has been a week now and pH is still steady at 7.4 with the fish doing wonderfully.
This product is available in grey or black. I chose the black in as much as a light surface would have turned dark anyway as algae collects. The black background provides a beautiful contrast for the colors of the fish; it has absolutely sealed the pond from leakage and, as indicated, totally prevented any alkali leach which would have resulted in high pH readings. In essence this compound establishes a "rubber liner" within the pond and provides a completely inert environment such as one would find in a five year old pond. This rubber is fiercely tenacious an once applied, will not peel thus offering an indefinite period of longevity. As an added benefit, it provides a very smooth surface which eliminates any possible abrasiveness to the fish. This product appears to be a definite winner for application to newly constructed ponds and biofilters where alkali buildup from new concrete is always an initial problem. I applied the rubber straight out of the can and used the TC-700 cleaner / thinner to maintain a soft brush between coats. Also, a high evaporative rate occurs with an open can of this rubber and the TC-700 cleaner / thinner was also employed to maintain a working solution.
In my estimation, Neoprene black rubber paint revolutionizes the building of ponds and filters by eliminating the problems associated with new construction. It is indeed, a blessing to be able to instantly age and leakproof block, brick and concrete. This stuff is great!