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H2O2 Dosing

2059 Views 15 Replies 3 Participants Last post by  mistergreen
What is the recommended dosing and process for using H202 for algae control?
Is it as simple as adding x amount of H202 to the tank or more of a direct method using a dropper and spraying directly on the algae?
Thank you
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The best effect is to spray or dip the algae while it’s out of tank water. If the algae is on the plant don’t expose it longer than 20 seconds or it will hurt the plant. On equipments and hardscape, the longer the better.

2nd option is to inject Directly At the algae while in the water. Leave the filter off for 30 minutes to an hour. Don’t exceed more than 1.5 ml/ gallon.

3rd option To dose the entire tank while the filter is off for 30 mins to an hour. Don’t exceed 1.5 ml/gallon.
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Be aware that dosing the entire tank (I have done this before) may knock back some of your plants heavily ("softer" plants, as opposed to thicker leaved species).
I definitely agree with mistergreen that the best way would be to remove the affected specimen (object) and treat is separately, if that is feasible.
Thank you both. I gave this a try today. I dosed H2O2 using a medicine dropper right onto algae areas with filter off for about an hour. I dosed total of 50ml as this is a 40G tank.
How many days should I continue this treatment for?
Wait a few days, the algae should turn red and die. If not, try again in a week. The H2O2 does hurt the filter bacteria a bit. That's one of the reason you turn it off for a time.
Don’t repeat. Give it a couple days to see if it worked. The algae will start to turn red and die. The exception is BBA, which takes a couple more days to see if it was harmed.
Sounds good, I'm going to wait a couple days. I did notice that my amano shrimp are suddenly eating BBA that I dosed, they weren't touching it before. So hopefully it's working.
Sounds good, I'm going to wait a couple days. I did notice that my amano shrimp are suddenly eating BBA that I dosed, they weren't touching it before. So hopefully it's working.
Yes, the BBA is dead and the shrimps are eating it.
Well, it seems to be coming back again and in force.
Scrubbing, syphon the debri and H2O2 the spot helps.

Fix your other issues too like too much micros/iron, light, CO2. If you have mulm in your tank, clean that up helps also clean the mulm out the filter.
Scrubbing, syphon the debri and H2O2 the spot helps.

Fix your other issues too like too much micros/iron, light, CO2. If you have mulm in your tank, clean that up helps also clean the mulm out the filter.
Accordint to Seachem iron test it's almost non-existent, even though I dose 2ml 3 times a week.
How do you know if there is too much micro nutrients? I dose 1/8tsp of Nutritrace CSM+B from aquariumFertilizer.com 3 times a week along with 2ml of iron. I know Nutritrace contains iron, so maybe I shouldn't be dosing extra iron?
As for CO2, drop checker stays almost yellow pretty much most of the time.
BBA is a pretty good indicator of too much iron. If your plants are hurting from too little iron, that's you indicator as well.
BBA is a pretty good indicator of too much iron. If your plants are hurting from too little iron, that's you indicator as well.
Interesting. I will stop adding extra iron.
Thank you so much.
Another question if you don't mind. I'm using a Finnex Panted+ LED light 36 inch. I have a glass hood on the tank to help limit evaporation. The light is sitting on top of that cover directly without the legs that came with the light. Is that the right approach or should I install the legs which will raise the light a couple inches?
I rarely get BBA in my low tech dirt tanks because I don't add ferts in the water. All the nutrients are in the substrate. Maybe you can add nutrients in the substrate and reduce water column ferts.

I have legs on the Finnex. An inch doesn't make a big difference.
What about light spectrum? The light I have has White, Red, Green and Blue lights. During the brightest times during the day it is using all of the colors. I read somewhere and Red and Blue spectrums can contribute to algae growth. Is that true?
Both plants and algae need light, blue and red so not sure where that theory came from.

Try reducing your CO2 too. Green is fine. No need for yellow.
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