Transition from winter to spring plays havoc on the lives and health of our pond fish under normal conditions. This spring, it seems is even worse than normal. It could be that winter hung on a little too long or hit much too early. Whatever the reason — we’ve had our hands full with water quality and fish health problems that normally seem easier to handle.

Ammonia from fish waste, dying plants and sludge in the pond is converted from toxic ammonia to nitrate (fertilizer for the plants) by a natural nitrification process. We refer to this process as the nitrifying cycle. Before this cycle can work properly two types of bacteria must be alive and strong in the filter and pond. Nitrosomonas is the bacteria responsible for converting ammonia to nitrites. Nitrobacter is the bacteria responsible for converting nitrites to nitrates. These two important bacteria die off in the cold waters of winter and build back up as the water warms in spring. If either bacteria is lacking in the ponds bio-filtration the nitrifying cycle does not function properly and if the water is warm enough for bad bacteria to grow and fish to eat and leave waste at the time the bio-filter is not intact both fish and plants can die.

Ammonia builds up and burns the gills of the fish and NO amount of ammonia in the water is acceptable. Death to fish is imminent unless a major water change is performed. Fortunately, if the fish survives the ammonia spike it should be able to recuperate.

If the filter has sufficient Nitrosomonas to convert ammonia to nitrites but not enough Nitrobacter to convert nitrites to nitrates fish and plants both die! Nitrites are a bit scarier than ammonia because once the fish gets nitrite poisoning it stays in the fish’s blood stream. Water changes, although necessary, do not simply do away with the irritant. Non-iodized salt in 3% solution can thwart the ill effects of nitrite poisoning but as soon as the water is changed and no new salt is added the fish can and do drop like flies! We’ve seen it happen too many times. Nitrobacter is the last of the two bacteria to grow. It requires warmer water temperatures. This is where we’ve been having most of our seeding problems this year.

It's inevitable that during this time of weather transition your pond will experience nitrifying bacteria growing pains.  Ammonia and nitrite spikes are two very dangerous growing pains.  Ammonia burns the gills of the fish and nitrites get into the fish's blood stream and can literally poison him.  Along with heavy water changes, there is something you can add to your pond water to protect your koi and goldfish.  Ultimate can be used to render the effects of ammonia and nitrites harmless up to a certain ppm (parts per million).  It also is a de-chlorinator so it can be used instead of de-chlorinators when making water changes or as an additive for it's protection abilities when not making a water change.  Testing is very important during this time.  Many of the water tests will not give correct readings when other ammonia inhibitor products are used.  That's why we like Ultimate.  We know the test will be right.

It's very important that you heat up the water sample when testing for ammonia in cold water - otherwise the test will not give you correct readings.  Place the test tubes in a warm pocket or hold them in your armpit until warm then perform the test.  

Beef Up the Bio-Filter

If you don’t have one, get one! If it’s not big enough to handle the fish load, increase the bio-filtration capabilities. Add filter material. Install another filter outside the pond. Click here to check out filter material.

Give Bacteria a Boost

There are products that actually work that you can purchase to help establish nitrifying bacteria in your bio-filter. You can use Microbe-Lift™ Spring & Summer to help establish the pond's balance for the season.  If you have a bead filter use Microbe-Lift's Bead Filter Bacteria formulated to give nitrifying bacteria a boost in bead filters.  These will not give instant results but will help boost the growth of the bacteria. We carry all these products at our store.

Turn OFF the UV

As much as we hate our green water we hate to lose our fish more! The UV light kills off some bacteria as well as sterilizing algae. Turn it off and suffer through green water for the time it takes to get the nitrifying bacteria established in the bio-filter. Once the bacteria is established you can feel free to turn the UV back on.

Stop Feeding the Fish

It’s tough to say NO to your children. For their own good, however, you must! By feeding the fish you are creating more waste which is ammonia. You can resume feeding them when the bio-filter is seeded.

Decrease Your Fish Load

Often we have more fish in our pond than the system can handle. If you didn’t add any fish since last year your fish have still grown in size. That equates to more fish load. Pick out your favorites and find homes for the rest!

Something’s going on this year. pH levels are going crazy. It doesn’t seem to be confined to any specific geographical area. We’ve never seen it this bad! 8 out of 10 water tests we’ve performed for our customers are coming back extremely high or extremely low. We’ve seen some that are off the charts. We don’t know why — perhaps because of low water tables our municipal water supplies are unstable — perhaps it’s acid rain. If you’ve never tested your pH before (or never had a reason to do so) you may want to do it now.

pH is basically the “feel” of the water. It affects both plants and fish. Too acidic (or too low) pH is like acid to the skin. Too high is too soft or cold. Although fish can tolerate pH of 6.8 to 8.0 it’s best to keep the pond between 7.2 and 7.8. Human beings have a pH level of 7.5.

pH constantly changes during the day. It’s at its lowest in the morning and highest at night. It’s those swings that make it a killer. Alkalinity, buffering and stability are all terms used to define how stable the pH is. An unstable pH could mean the difference between a complete fish kill or no problems at all.

Test your pH 3 times per day (morning, midday, evening) during this transitional time of year. If it’s too high — add 1 tsp. of vinegar to the water each hour until it lowers down to an acceptable reading. If it’s too low — add 1 tsp. of baking soda each hour until it comes up to an acceptable level. Then stabilize it! Do NOT bring it up or lower it too quickly unless it’s an emergency.

An emergency is a pH “crash” of 6.0 or lower. One indication that you may be experiencing a pH crash is if the skin of the fish appears to be peeling or if the cap of your Oranda appears as if it’s been eaten away. Change the water immediately if you experience a pH crash then make sure you adjust UP (for acidic low readings) or DOWN (for too high alkaline readings) and stabilize the new water using pH stabilizer.

Plants and fish both need dissolved oxygen in the water to live. Cold water holds dissolved oxygen better than warm water so fish that made it through winter without a problem may experience one now if the pump is not running continuously. If you have fish in your pond do not make the mistake that many make by turning off the pump at night. The term “oxygenating plants” is a misleading term. Plants give off oxygen during the day but take it back at night. A planted water garden that doesn’t run at night spells disaster for its fish inhabitants. It’s not unusual to lose every fish in the pond overnight.

Even during the day (especially at the hottest time of the day) you may notice signs that your fish are not getting enough dissolved oxygen. If they gulp at the surface of the water or hang around the water return it could mean that either the fish’s gills are under attack from parasites and/or disease or there is simply not enough dissolved oxygen in the water. In both instances increased oxygenation is warranted. Either add a fountain or air compressor with air stone or manifold.

Chemicals that claim to “clear up water” and even some medicines used for treatment of fish illnesses can rob the water of all its dissolved oxygen. Be very cautious when adding any kind of chemical or treatment to the water. Read the label well. Our rule of thumb is that if the label warns you that it could be dangerous — expect it to be dangerous! Don’t use chemicals during the hottest part of the day or in the evening or at night. If you see the fish begin to gulp for air immediately change the water. Never turn off the pump during a treatment and add aeration if possible.

Fish are not the only life affected by low oxygen levels. Desired plants in the water garden, such as water lilies, can be smothered out by algae and other weeds that further zap the oxygen and nutrients. Mosquitoes thrive in low-aerated situations. Natural community ponds are affected greatly by problems that low-oxygen levels bring. Simply adding a large aerating fountain to the community pond is normally all it takes to alleviate many of the problems.

Parasites and bad bacteria such as aeromonas and psuedomonas thrive in cooler water temperatures than the upper 60 degrees needed for the fish’s immunity systems to become fully operational. This is truly the worse time of year for the fish. If there are any health problems with the fish at all it is during this transitional time that it will surface.

Thoroughly Clean the Pond — This is the best time to take the sludge off the bottom of the pond. Sludge makes great living quarters for parasites and disease.Click here to get more information on cleaning the pond.

Feed Antibiotic Food — When the water temperature reaches 64° feed only antibiotic food for two weeks to ward off any underlying infections. A great one to use is The Doc’s Prescription™ Triple Antibiotic available exclusively through us.

Perform a Salt Treatment — This will kill many of the most common fresh water fish parasites and helps produce a protective slime coat for the fish.  Click here to find out how to perform a salt treatment.

Watch for Signs of Ulcers and Infection — Red sores cannot heal if the immunity system is not functioning. If any redness that is not the color of the fish is seen that means you have an ulcer beginning.  Use Tricide-Neo dip or Little Dab-a-Do scrub as directed on the label for each fish affected.  You might also want to treat the whole pond with Anti-Bacteria - just be sure to follow directions and do not run the treatment through your biological filtration because it will kill the good bacteria too.

Treat for Parasites — If you suspect your fish have parasites then, by all means, treat the pond.  If you do not know which parasite it might be then treat for both. We have put together a Parasite Pak that makes your life easier.  DO NOT use two types of chemical treatments at the same time.  You would treat for Ick first then flukes or vice-versa but never together.

If any new fish was purchased in the Fall it is possible that anything that new fish could have been carrying will surface now that the water is heating up. Even if you followed every rule of quarantining the new arrival — if the fish was quarantined during the time when the weather was cooling down it is possible that a disease is waiting until the water heats up to show its ugly head.

Algae bloom!

Algae bloom is not dangerous to the fish. They love it. The only health risk is that we cannot see the fish to make sure there are no signs of disease or injury. String (or filament) algae, blanket weed and the algae that accumulates on the sides of the pond are not considered algae bloom and are covered in a separate section.

The simple answer is to install a UV. The not-so-simple answer is to try to balance the pond naturally – notice I said “try” Sometimes it’s better just to bite the bullet and install the UV.

Materials Needed: Plenty of plants and plenty of patience!

Free-flowing algae are microscopic plants. Higher forms of water plants compete with algae for nutrients in the water. It’s our hope that the water lily wins! The best plants for the job are: Anacharis, Water Hyacinths, Water Lettuce, Parrots Feather and Water lilies.

Get Rid of Excess Fertilizer

The junk on the bottom of the pond feeds algae. Clean it up — Get rid of it. Also use Microbe-Lift Sludge Remover during the year to help keep the sludge away.  Use pellet-type water plant fertilizer designed to be pushed down into the soil instead of a liquid fertilizer. Slow down the amount of food you are feeding your fish. The more they eat. The more they poop.

Give it Some Shade

I personally do not like adding color to the pond water but there is a safe blue dye that can be used to filter out some of the sun. Water lilies and other floating plants such as hyacinths offer shade.

Do NOT Change the Water

Every time the water is changed it starts the cycle all over again. It’s best to let it go — turn your back on the green if you must. It will get worse before it gets better.