new tank syndrome – Aquatic Veterinary Services

The #9 Mistake – Adding Fish Too Early

You have a plan, you got your tank and all the additional items, so it’s time to add the fish! But how many fish do you add? In what order do you add them? In the beginning, your biggest hurdle will be establishing your nitrogen cycle. This cycle is made up of commensal bacteria living in your substrate and biological filtration media (sponges, matting, bio balls, ceramic cubes etc). These helpful bacteria convert the primary fish waste of ammonia into nitrite and from there into nitrate. Ammonia and nitrite are highly toxic to fish, and can cause lethargy, loss of appetite and death.

When a tank is brand new, the bacteria have not been colonized. There are many commercial starters promising to “instantly start” your tank, but they are the aquatic equivalent to snake oil. Our office tested over half a dozen of these products with no decrease in time to conversion. You do NOT need to add these products to your tank, they will come with the fish; they just take time to become established. It will take 4-6 weeks for your tank to go through all the necessary steps to become established. If you follow your tank’s progression with your water quality testing kit, you will yield a graph like this:

You will see spikes in ammonia, nitrite and then nitrate. When you see this DO NOT PANIC. It is a normal occurrence in EVERY new fish tank. It is called “New Tank Syndrome” and there is no way around it unless you have another established tank with similar water parameter requirements that you can steal some filter media from.

The best way to combat New Tank Syndrome and avoid crashing your tank with a major ammonia spike is by starting with just a few fish in your new tank. Start with one or two goldfish or 3-4 tropicals, like zebrafish or tetras, before your tank is established. Slowly increase your fish levels from there and you will never have an issue.

Be patient! It is extra work, but I guarantee by following these steps, you will not lose a fish from New Tank Syndrome. Buy a test kit, know how to use it and don’t panic when those spikes hit. By having fewer fish in a larger volume of water, you will produce a smaller, more tolerable spike, keeping your fish alive.

Top Fish Mistake #2: Disorganized Cleaning

How often do you clean your fish’s home? Do you have a regular schedule or do it whenever? No matter what kind of fish you have in either a tank or a pond, a routine cleaning regimen is essential to good fish health.

Go through the following checklist and see how much you do:

Clean filtration by backwashing sand or bead filter or rinsing or shaking matting or bio balls
Scrub the sides of the tank/pond
Clean the bottom of the pond using a vacuum or gravel siphon your tank
Water change through backwashing or siphoning
Check water chemistry using a drop-based test kit

If you’ve never heard of some or any of the above checklist items, now’s the time to start. Buy the equipment you need to get going and start with removing about 10% of the tank/pond water every other week. Get your kids or help or hire a maintenance service if you are unable or don’t want to clean it yourself. Purchase a test kit so you can follow your water chemistry as your system changes. Buy a test kit here.

Minimal or no system cleaning can lead to “Old Tank/Pond Syndrome.” In these cases, the water has sat around for so long that it’s eaten up all of its buffering capabilities, sending your pH crashing into the 6.0 range. Your fish are fine for now, since they’ve slowly adapted to the change and the low pH protects their gills from absorbing the toxic levels of ammonia wafting around your system. But I bet you’ve seen some low levels of chronic disease and death for the last few months? Don’t just go dumping a bunch of buffers or 100% water changes and expect your fish to survive! When correcting this problem, slow and steady water changes are what will get your fish through this problem alive.

If you do everything on our checklist, and on a regular basis, we are so thrilled to hear it! But did you know that you could be over cleaning your system if you do it too regularly or too thoroughly? Your filtration needs to have some layer of scum on it where those good bacteria can live and thrive. If you blast your filters until they’re pristine, you’re hitting the reset button on your whole filtration system. It’s the same as starting with a completely new system. It takes 4-6 weeks minimum for those good bacteria to start colonizing your filters. You can try quick start bacteria products, but we’ve tried them ourselves and seen no escape from that 4-6 week time frame.

Similar to not cleaning enough, over-cleaning can resemble “New Tank/Pond Syndrome.” In a system where bacteria have not been able to colonize or are never given the chance, you’re looking at a lot of ammonia and nothing else. No nitrite or nitrate will appear in your testing until those bacteria get to munching. In order to avoid this, try to avoid over cleaning with your trusty power washer and instead give your filtration a good shaking or very light rinse.

Here’s our friend, the Nitrogen Cycle, for reference.

Your maintenance regimen will vary with daily to weekly to monthly chores. Clean off floating debris daily and check your skimmer. Always check that your equipment is functioning properly. Make sure you have the contact information for a pond professional on hand to help with any emergencies. Follow our checklist for every two weeks to start, then start extending it by a week and keep an eye on your water chemistry. This will get you on the path for good water quality and happy fish!