DC634
Aquarium Advice Apprentice
Based on the pictures can you tell what the issue for these two plants are? I think calcium deficiency for swords and no idea for fern.
Looks like a lot of algae to me as well, maybe come cyanobacteria too.
It also looks like the tanks are very lightly planted, and not under the highest of light, which means slower growth. You are adding a tremendous amount of fertilizer given the growth and plant mass you have.
CO2 will certainly help, I suggest the following:
Reduce light intensity if possible.
Reduce photoperiod to 5 hours per day max (until algae has subsided, then slowly increase back up to 8 hours per day over a few weeks).
Ensure you are providing adequate nutrients for the plants (unhealthy plants promote algae). Thrive is a good option, and given your NO3 levels aren't out of whack, going with a modified EI "light" dosing regime using Thrive would be a good start. Use the website to determine how much Thrive to dose to achieve a leaner dosing amount:
https://rotalabutterfly.com/nutrient-calculator.php
Dose Flourish Excel or equivalent Met14 at the “after water change” rate on the Excel bottle once per day.
Manually remove all algae you can.
Manually remove excess organics in the tank by gravel vacuuming and cleaning filter media in old tank water every water change.
Manually remove any decaying or dead plant matter.
Increase water change frequency, and the amount of water changed.
Consider spot treating badly affected areas or dipping plants / hardscape in a Flourish Excel, Met14 or H2O2 + water solution. Google search which method you think would work well, and for general ratios to mix a safe solution. Certain plants can’t tolerate these chemicals, so ensure you do a little research prior to dipping / spot treating plants.
If using CO2, ensure CO2 is dropping the pH of the tank water a full 1.0 – 1.2. To do this, measure the pH of tank water with no CO2 dissolved in it, and then measure again 2-3 hours after CO2 has been running. Ensure the drop in pH is a full 1.0-1.2. If the drop is not there yet, slowly up CO2 over a few weeks until at least a 1.0 drop is achieved, and watch fish / livestock carefully. Adjust CO2 down if you notice fish gasping at the surface and consider running an airstone at night when pushing a 1.2 or greater drop. For example, a tank water pH of 7.5 with no CO2 dissolved in it, should reach a pH of 6.5 – 6.3 for CO2 to really shine, and for maximum plant health.
Consistency in CO2 levels is key to plant health. Keep CO2 levels as stable as possible once a desirable level has been reached.