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6 Reasons Your Tank pH Keeps Dropping!

There are a huge number of beginners to the fish keeping hobby out there right now after the large spike in interest the hobby has seen in the last two years pulled a wide range of people in.

This has resulted in a number of questions being asked every single month based on various problems that people are having with their tanks no matter their setup or the species of fish they keep.

One thing that we see people having problems with time and time again in their water parameters and more specifically, their pH levels.

Many people try to mimic the tank setups of their favorite influencer in the fish keeping community without realizing that many of the decorations and substrate options out there can cause their pH to spike or drop.

This is why we have decided to publish this article going over the most common reasons that your tank pH keeps dropping to try and help as many of our readers as possible. We also have an article going over using crushed coral to raise your pH that will be helpful to checkout for anyone that is having issues with their pH levels dropping time and time again.

Why Your Tank pH Keeps Dropping!

Here are the six most common reasons that your tank pH keeps dropping no matter what you try to stabilize it:-

  • Soft Water Sources!
  • Driftwood In Your Tank!
  • Issues With Your Substrate!
  • You Have Seashells In Your Tank!
  • Overfeeding Your Fish!
  • The Death Of A Fish In Your Tank!

If you are new to the fish keeping hobby then the chances of you having two or more of these problems with your tank are actually surprisingly high so try to check for multiple problems!

Soft Water Sources!

The tap water in many areas is not suitable to maintain a stable pH even if you use a tap water conditioner product.

Soft water is definitely the most common reason that pH levels in an aquarium will be unstable and many people can often work on improving the overall hardness of their tank’s water to fix the issue.

Thankfully, there are a number of products on the market these days are can offer a quick and easy way to stabilize tap water to maintain a consistent pH in your tank so although this is a common problem, it is cheap, easy, and quick to fix.

Driftwood In Your Tank!

All driftwood will have some effect on the pH levels in your tank but properly prepared driftwood will change your tanks pH level much slower than random driftwood that you found yourself.

We know that driftwood is very popular within the fish keeping hobby right now and that many people use it as a part of their aquascape but this can be the reason that you are having problems with your pH level.

This is largely due to many people just finding random driftwood at the beach or local river bank, taking it home, splashing some water over it to get the dirt off and then adding it to their aquarium.

Any self-found driftwood should be soaked in a body of water for a couple of days before the water is replaced with fresh water and the driftwood is resoaked. You then test the water parameters of this second batch of water in the tank to see how it does before even considering adding it to your aquarium.

Another benefit of this method is that it can also drastically reduce the tannins that the driftwood will release into your aquarium water too.

Issues With Your Substrate!

The substrate that you have at the bottom of your tank can also play a big part in the tank’s pH levels if it is not properly chosen or installed.

We recommend always using an aquarium-safe gravel or sand as these will not affect your tank’s pH level and they are much easier to clean than many of the other substrates on the market.

If you are a beginner, we really would recommend that you avoid using anything else as your substrate until you have a couple of months fish keeping experience under your belt as an absolute minimum.

As we mentioned earlier in the tank, many beginners try to emulate the tank setups of some extremely experienced fish keepers who have decades of experience in the hobby who use more troublesome substrates but these can cause issues.

You Have Seashells In Your Tank!

Seashells are very popular to use as a decoration in many aquariums these days and they can often be bought very cheaply from your local pet store.

Although they look great in an aquarium, it is important to remember that seashells are made from calcium carbonate which will affect your tank’s pH levels.

In a similar way to driftwood, seashells that you find yourself can have a higher risk of causing problems with your pH levels in your tank but our article on how to keep seashells in your aquarium should be able to help you prep the shell correctly for use and avoid any problems with a pH levels that keeps dropping.

Overfeeding Your Fish!

Overfeeding your fish is actually one of the most common problems that we see here at Pawfect Pawprint and it can often be the reason behind a number of different problems in your aquarium, not just pH levels.

One of the issues that overfeeding your fish can cause is an ammonia spike in your tank which will lower the tank’s pH levels.

You should always try to avoid overfeeding your fish if possible but a cheap gravel vacuum will often be enough to quickly remove any leftover food that is sat on your substrate to prevent problems moving forward.

The Death Of A Fish In Your Tank!

The death of a fish in your tank can cause a wide range of problems with your tank’s water parameters and an unstable pH level is just one of them.

Whenever a fish dies, the ammonia levels in your tank will begin to spike which can often cause problems with your pH level if it is not dealt with quickly.

You should always remove any dead fish from your aquarium as soon as possible and we would also recommend carrying out a partial water change to help stabilize the tank’s water parameters.