Water Quality

Give Your Water A BOOST!

Whether you have a Koi Pond, a Water Garden, or a Water Feature with a couple of Goldfish in it for your garden ideas for your home remodeling plans, the main ingredient – water – needs some extra attention during these hot summer days. With air temps around the century mark, and pond temperatures nearing 85F – we’re in a danger zone which can have serious consequences for our fish. Evaporation of pond water can also lead to problems. Here are two ideas which will make a difference in your water quality, and lead to happier fish and clearer water.

The amount of oxygen saturated in the water changes with the temperature, and is a major factor in the health and well-being of our fish. During colder seasons, water can hold plenty of oxygen for our pets. But as water temperatures climb near the 80’s, much less oxygen is saturated in the water. This leaves a minimal margin of safety for the fish. If you ever see your fish “sucking air” at the surface or near the waterfall, especially in the mornings, then your oxygen saturation is borderline. I’ve said that warmer water holds less oxygen, but I have not mentioned that there is lots of competition for the scarce amount of oxygen that is available. Besides your fish, plants and algae also consume oxygen. In fact, you probably know that the process of photosynthesis causes your plants to produce O2 during daylight, but at night, the reverse is true – the plants use up oxygen. So that means that early in the morning, oxygen, which has been taken up by plants during darkness, is at its lowest point of the day. Fish deaths from oxygen starvation are highest on summer mornings. This is a serious situation and demands our attention.

So how do we add oxygen to our water? Actions that cause great disturbance to the surface of the water are the best. Waterfalls should be left running all night to add extra O2. Air stones in the pond not only add air bubbles underwater, but do double duty by creating a welling up of deeper water to the surface for oxygenation. Anything that creates splashing or surface movement is adding oxygen. Here’s a simple DIY project that will do the job really well.  What you are going to create is a spray bar that will use some of the return water from your pump and spray it over the side of the pond to really agitate (oxygenate) the water! The spray bar is a piece of ¾ -1 inch PVC pipe about 3-4ft long with 1/8 inch or smaller holes drilled every few inches along the pipe. Put an angle somewhere along the length to be able to anchor it on the side of the pond. Hook up a hose from your pump to one end, and a cap on the other end. Water from the pump will shoot out the holes in the spray bar – so position the spray to create as much splash as possible. Voila! Oxygen saturation goes up – and your fish will enjoy playing in the water streams. Increasing the amount of oxygen in the water is the BEST thing you can do for your fish!

Another action that will really improve your water is by doing small water changes. There are lots of harmful substances in the pond water besides Ammonia, Nitrites and Nitrates. You can test for those with test kits, but some of the other substances are unseen and hard to measure pollutants. Remember, your fish are swimming in their own toilet, and besides the solid wastes there is discarded slime coat, decaying plant and algae debris and dust and pollen blown in by the wind. All of these materials break down to what is called Dissolved Organic Compounds (DOC), a fancy name for decayed organic matter dissolved in your pond water. Do you remember when your water was new, clear, and had a sheen to it? After a while the clarity became less, and the water takes on a yellowish-brown tinge – you may also see foam or bubbles around your waterfall. That tinge and those bubbles are DOC – your pond is polluted! So, to help cure this problem, remember this saying – “The Solution to Pollution is Dilution”. We can empty 10% of our water every week, and add new (dechlorinated) water. Don’t think you are doing a water change when you “top it up” after water levels fall from evaporation – it’s not the same. Evaporation actually concentrates DOC by removing water molecules, but leaves the DOC behind. You must remove the DOC by dumping pond water. After a while, you will dilute the pollutants and notice a change in the “look” of your water. It makes a big difference.   Best wishes to your fishes.