A Generally accepted method of spot dosing with H2O2 (Hydrogen Peroxide)
We will work with a 30cm cube to make all calculations easier (30L of water) and be using 3% solution of H2O2
Remember you are playing with a chemical that oxidizes when it comes in contact with organic matter, so always use as little as possible as overdoses can damage your invertebrates (shrimp) or nitrifying bacteria causing your tank to cycle again.
MAXIMUM dosage in a 30L body of water is 15ml in a 48 hour period, this will increase total peroxide levels by 15 mg/l, generally this is deemed safe, but always best to work well and truly under this level.
Things you will need:
Half hour of time
Hydrogen Peroxide (3% solution) - easily purchased from your local super market or pharmacy
1x 10ml syringe, these are available relatively cheaply from your pharmacy
Prepare your tools:
Draw up 5ml of your H2O2
If this is the first time you're doing this, before you start the actual dosing process add 2.5ml of tank water as this will give you slightly more ammo to play with without increasing your overall dose.
Prepare your tank:
Turn off all filters and pumps.
This is so you don't have a current in the body of water (should only take 30seconds to settle). also if your dosing near your intake best to avoid getting H2O2 in the filters as it will go bananas on all the good bacteria you have in there.
Plan your attack:
Take a step back look at what your treating and figure out if you have more than one place to dose or if its just localized less time your filters are off the better.
Not an Ideal situation to be fiddling around for an hour with your filtration off
Dose sparingly directly above the site you wish to treat, within a second or two you will see it bubbling away. try to avoid sensitive mosses and such if in doubt patch test first.
An example of what the effect is:
Wait a couple of minutes and turn everything back on.
It is generally suggested to do a water change (one third) if you wish to re-dose within 48hrs, but as we are only playing with a third of the maximum dosage you can repeat this the next day if you feel it necessary, or if you have more algae than this dosage allows you to treat.....
Good Luck and if in doubt ask questions on the forum, there is plenty of experienced shrimp keepers that are willing to help out!!!!