• Take your bucket and pour in the required amount of substrate you wish to use, between 1cm to 2cm (half inch to just under an inch) coverage of your tanks base works best. Pour in RO water which should cover the substrate in the bucket by about an inch and start to swill and stir your hand around in the substrate, this cleans and removes and dust, dirt and debris. By removing this you will get clearer water quicker and in the future if you disturb the substrate in your tank during maintenance it won't kick up dusty water. Once satisfied pour away the RO water and repeat this step until you are happy with the cleanliness of the water you are pouring away after the wash.

• SLOWLY and CAREFULLY add the washed substrate to your tanks base by hand and spread evenly, you don't need to compress it or apply pressure because this could crack your tank.

• Take your rocks or ornaments and complete the same steps as above in point 3. By now you should be seeing that anything that goes into the tank must be rinsed and cleaned in RO water prior to going into your tank, pour away the dirty water and goto the next step!

• Take your rocks and place them in your tank, I would advise you to make sure the rocks are not touching any of the glass in your tank (including the base) if you are going to stack them up high as this will apply alot of pressure to the glass and could crack or weaken the integrity of the tank (with nano tanks you dont really need to worry about this as you wont wont fit a HUGE amount of rock in the space provided). Make sure the rocks are set in the substrate where they will not rock over or sink lower into the substrate over time as this could trap and crush the shrimp (Don't push too hard downwards into the sand though!)

• After the addition of your rock scape, now is the best time to organise and arrange the rock layout to your liking and moving things around for the last time, be sure nothing is unstable or is in danger of moving once water is in the tank. You can also add your heater to the tank if you are going to use one, Take your heater and suction cups and give them a quick rinse/clean in some RO water, next add the heater to your tank which MUST be completely submerged with just the wire running out of the water, don't plug it in or switch it on until it is fully submerged. You can set the temperature of the heater by turning the dial on the top and watching the front display, this shows the temperature the heater is set to switch on and keep the tank water temperature stable to. As a general rule you may need to set the temperature a degree or 2 above what setting you want e.g. You are aiming for 20degree C water in the tank so set the heater too 21.5. This makes sure the water which is furthest away from the heater also stays at around 20 degrees C. If you don't compensate slightly you may notice the heater switching on and switching off again once it detects the water directly around it reaches 20 deg C but on the other end of the tank the water sits cooler thus avoiding cool spots.

• Take your RO water and slowly pour it into the tank, I'd advise pouring into the sand and not onto your rocks as this may push them down too much. Don't worry about the sand moving as you can re arrange it after the tank is full, you can even add a plate or cup to the sand and pour the RO water directly onto it to deflect the splash caused thus keeping your substrate in place during the tank filling phase.

• Next take your packet of marine salt and check the back of the pack for the salt to water ratios, off the top of my head the Instant Ocean marine salt weighs in at 330grams per 10 litres of RO water to make marine salt water (1.020 SG) we want roughly just under half strength salt water to make brackish water.




• You can use the calculator below to input your tanks volume and required SG and it will tell you how many grams of salt to use. Or if you are feeling lucky you can guesstimate it and adjust later, we want a SG between 1.008 up to 1.015.

LINK: Online SG/Salinity calculator can be found here
• If you are just going to roughly guess the salt quantity to make brackish water and are using Instant Ocean marine salt then I would take 10litres of RO water and add 170grams in weight (good starting point) of salt directly, mix it in by stirring the water and wait for it all to dissolve. If you are using a 20litre tank then add double the 170grams of salt (340grams) and so on, don't worry about the salt sitting on the bottom of your tank as it will dissolve on its own. You will need to tweak the results later so dont worry too much about getting it perfect at this stage.

*Please note that this is the only time you can add salt directly to the tank as you don't have shrimp/snails in there yet (direct salt contact can be very bad got tank life). In future you will need to mix the salt and water in a 10 litre bucket prior to adding it to your tank after all salt has dissolved.

• Next step is too add your lights (if you haven't already) and tank lid, leave the lights on and let the tank settle. We are waiting for the salt to completely dissolve and the water to get to the correct temperature for a day or so before we measure the SG/Salinity of the salt water. *note: the reason we wait for the tank water to reach the set temperature before measuring the SG is because cold salt water will give you a different reading to warm salt water, being brackish water, in theory doesn't matter if it's slightly under or over which you aim for but I like to do a job correctly :)

• Take your hydrometer or refractometer and place a sample of your tank water on the device to take a reading of your current SG/Salinity, as stated above you really want a SG/Salinity reading between 1.008 and 1.015 so if you are under or over this you may need to add more salt to raise the SG or remove a few glasses of your tanks brackish water and replace with pure RO to dilute the salt content. If you do alter the water re-measure with your meter again, if changes are needed beyond this then rinse and repeat until you have perfect brackish water for Opae ula shrimp.




The above 2 photos are examples of how a Refractometer and Hydrometer will display your waters SG/Salinity. (the SG/Salinity shown above isnt the required level needed for brackish water but merely an illustration)

• Its important to switch your lights on for 12 hours a day and off for 12 hours to promote algae growth, but not an excessive amount as it can look unsightly. This algae and biofilm grown is the food for the Opae ula shrimp! You can use a timer on your light's plug socket to switch it on and off automatically to avoid over or under exposure from forgetting to manually switch the light on or off . Usually it will take a month to 2 months for your tank to cycle, grow algae and contain all the beneficial bacteria needed in the water to keep the tank healthy.

• While your tank is 'maturing' the water in your tank is going to go through a few different stages which are all part of the nitrogen cycle, you can see if the cycle has completed sucesfully by using a water test kit on your tanks water when you start to get some brown or green algae growth. A zero Ammonia, Nitrite and a Nitrate reading of 10ppm or below is required and if so the cycle is complete and you may introduce some Opae ula shrimp and snails to your tank!

• You can speed up the cycle process by adding matured Opae ula tank water, algae or substrate from another keepers tank which will reduce the the wait by roughly 50%, but you may still have to wait for signs of algae to show up in the tank prior to adding shrimp.

• You can read more about the Nitrogen cycle and tank cycling HERE

• If you dont have a water testing kit then all you need to do is wait for brown or green algae to start growing in your tank and once this stage is achieved then it is time to add you Opae ula shrimp and snails as there is a *decent* chance the cycle is complete and all is well.