If you want to add the CaribSea Eco-Complete, which has been renamed to Eco-Planted, to an already established fish tank, then you can take a look at this guide from Aquarium Blueprints to see how you can properly do so.
How to add to a bare bottom tank
If your established aquarium doesn’t have a substrate, then we recommend using a cup or scoop to carefully place the Eco-Complete or Eco-Planted at the bottom. You can also use a water bottle.
Before doing so, make sure you lower the water level by taking out some of the tank water; otherwise, the substrate will increase the level and may potentially cause the aquarium to overflow if you aren’t careful.
Make sure you release the substrate as close to the bottom as possible to prevent the sharp edges of these small rocks from potentially damaging the glass or acrylic panels.
Of course, you should also make sure that your fish or other aquatic pets aren’t in the way. You may want to consider re-homing the inhabitants temporary when you add the substrate.
How to top off an existing substrate with Eco-Complete or Eco-Planted
The same steps we mentioned above for a bare bottom tank should also apply if you want to top off Eco-Complete or Eco-Planted with an existing substrate.
The only step we recommend adding is that, if you have live plants that have been rooted in the existing substrate, then we recommend that you take it out of your tank. You can replant them once you are done topping off the substrate.
How to replace the existing substrate with Eco-Complete or Eco-Planted
In general, we don’t recommend replacing your existing substrate with Eco-Complete or Eco-Planted. This is because the old substrate contains a lot of beneficial bacteria that will help your aquarium stay cycled. So, if you remove a large portion, then it can cause spikes to ammonia, nitrites and nitrates in your tank water.
Therefore, you are better off mixing Eco-Complete or Eco-Planted with your current substrate.
If you absolutely need to replace the existing substrate, then you can try doing the following:
1. Remove the old substrate from your tank. CaribSea recommends removing no more than 10% of the substrate per week in order to minimize the potential negative impact of your biological filtration.
2. You can then add the equivalent amount of Eco-Complete or Eco-Planted to the tank.
3. As an extra precaution, we recommend using a product like Seachem Prime, which helps detoxifies ammonia, nitrites and nitrates for a limited time in case your biological filtration gets affected.
You should also test your tank water occasionally. If you notice an increase in these nitrogen compounds, then you can do water changes to dilute these toxins until your beneficial bacteria colonies are built back up again.
4. Repeat the previous three steps for 9 more weeks until you completely replace the old substrate with Eco-Complete or Eco-Planted.