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Ammonia Warning!

If you discover ammonia in the top off water, do you know what to do?

Heads up, everyone.  Your livestock could be at risk.  This is no joke; a few nice tanks full of corals have suffered from the additives cities are dumping into our drinking water to make it safer for human consumption.Our bodies are able to deal with this stuff usually, but our livestock is far more demanding by comparison. 

Something we rarely test is ammonia, a test kit relegated to back of your closet after the tank’s cycle has completed.  Fish start to die, and we retrieve it.  But when your fish are fine and corals are declining, you often check alkalinity & pH levels, as well as salinity.  I’m recommending you find your ammonia test kit TODAY, and immediately start testing your waters: tap water, RO water, DI water, and newly mixed saltwater.  If you discover ammonia in the top off water, do you know what to do? 

API’s ammonia test kit works for fresh water and saltwater, and is affordable at $10.  When I recently heard from a club member that his corals were dying, we discussed his water conditions.  We had much in common:  same RO/DI system, same city water source, same volume of water in our systems.  Frustrated, he added additional stages to his RO system to help take out chlorine and ammonia to make the water safe for his livestock.  I decided I better test my water as well, if nothing else than to rule out that this wasn’t an isolated case.

Collecting a small sample of tap water after letting the faucet run for 30 seconds, the kit indicated 1ppm ammonia.


Next I tested the water coming out of the 150gpd membrane of my RO system: .5ppm My next test was after the DI section, which also was .5ppm instead of zero.  Ammonia can pass right through DI resin if the level is high.



Every drop of top off water was adding ammonia to my tank if left unchecked.  My system needs 3.6 gallons of top off daily to replace evaporation, so ammonia at this level wouldn’t be toxic, but it begs the question: when it is too much? What about those that rely upon evaporation to cool their tanks using huge fans?  How much toxic top off water are they adding? 

Rather than risk hitting that tipping point, I immediately dosed my top off water with Seachem’s Prime, and lowered a sterilized powerhead into the 45g reservoir for 9 minutes to make sure the dechlorinator was thoroughly mixed in. 

Once that was done, I tested my reef’s water, and was happy to read that it measured 0.  Whew, caught it in time.

 Since discovering this situation, I called my local fish store to warn the store owner that the water he was selling was likely at risk since he’s within walking distance of my home.  He opted to add some Prime to his water for the time being to make sure his customers are well cared for.  Two more friends reported sudden coral losses, and were advised to test for ammonia immediately.  Both of these individuals were doing water changes trying to fix the situation, which only made things worse with the rising ammonia levels. 

I don’t know if this is a nationwide issue, but for those suffering drought conditions due to the dryer summer months, the fact is that water tables become increasingly contaminated due to the dwindling water supply.  Those of you with tons of rain may experience changes as well.  I’m imploring you to do all the tests and don’t assume your locale is immune.  Better to know for a fact and continue to enjoy your aquarium rather than assume all is well and find yourself struggling to correct a crashing system. 

If you discover you have trace levels of ammonia or chlorine, Seachem’s Prime is the perfect product to lock it up in both top off and newly mixed saltwater.  For years I’ve recommended every hobbyist keep a bottle in their arsenal for emergencies and this is definitely one of those times.  I don’t know its shelf life, but I always buy a brand new bottle annually.  One capful treats 50 gallons, making it quite economical.  It is safe with your livestock.  Here’s the official link: 

For the time being, I’m going to be adding Prime to all the water going into my tank until conditions improve. 

Feel free to share your results, either to forewarn or to assure others what the current conditions are in your area.  Be proactive and talk with your club members to make sure they are aware of this possible risk.  Do it now, the reef you save may be your own!