Reefkeeping made easy- what was not explained.

here is one of those things that is not explained when first starting up a system. i thought i touched on this earlier, but i could not find it.

the nitrogen cycle is not the only process that occurs when a system is first started up. in fact i think that it is far less important than we are led to believe. this process is all about ramping up bacteria. the bacteria is already there. it only needs to food. it takes very little time for the bacteria to match what is in the system. i would be very surprised if it takes over a week for the bacteria to ramp up for any reasonable bioload change. yet this seems to be what everyone is most concerned about. do not get me wrong, making sure that there is not any ammonia and nitrite in the system is important, but i would bet that to get any ammonia or nitrite in any appreciable amount there must be something majorly bad going on in the system.

which brings me to the most noticeable process/cycle that goes on in our system. the silica and phosphate processes. both of these can lead to what i call the uglies. the uglies tend to start about 2-3 weeks after the tank is setup and can last several months depending on the amount of nutrients that were released during the setup process. the biggest culprits of this are silica, used by diatomic algae, and phosphates, which we know is used by cyano and other algae. both of these food sources are released during the mechanical process of setting up a system. phosphates and silica are everywhere. as bits of sand and LR rub against each other they break off little bits. these little bits allow the silica and phosphates to become loose in the water column. the more sand/LR the greater the chance of having more of these available right after the system is setup.

lets talk about silica. diatomic algae, the main algae you keep scrapping off the glass is diatomic. it uses silica in its body structure. in the beginning of a system, diatomic algae is the only real user of silica. it quickly is able to ramp up and bloom to use up significant amounts of the silica, hence the brown algae bloom encountered. over time as the tank matures the sponges will start growing under the LR. these sponges also need the silica and will quickly start uptaking the silica making it less available to the diatomic algae. soft corals and i believe LPS also use silicates in their structure. these critters bind up the silicates long term unlike the diatomic algae which reproduce and die fairly rapidly releasing and uptaking the silicates. until these binding organisms take off the diatomic algae bloom will continue.

out of time for now. i will get to the phosphates when i am back on.

G~

Brad65ford said:

Geoff, is there any way to avoid the new tank syndrome / bloom cycle?

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not entirely. if you rinse the items going into the system very well then you will remove most of the nutrients that will become immediately free.

if you are using base rock, then make sure to get anything loose off. during transportation the rocks bang against each other and can create a lot of loose material.

the sand is always going to be a balancing act. the more you rinse the more they grind against each other releasing more dust. it is good to give the sand a good strong rinsing to get the vast majority of the fines away. after that it is up to you to decide when to stop rinsing. you can go on forever and then end up with nothing.

it is also very important to start with clean water. this is probably going to be the biggest batch of water you will add to the system. not putting in clean water at this point could really start the bloom off. what comes in on this water is immediately available to anything in the system.

G~

sorry, had a busy weekend. phosphates

phosphates are a bit different. they do not really cycle, they kind of flux. they get bound and then "released" as organisms die and "feed" on them. bacteria are the fastest at being able to use them. then come the algae. phosphates come in through all kinds of means as we talked about earlier in this thread, here we will talk about the initial load of them and how they help cause the "uglies"

here you have this great empty system with all of these phosphates just floating around in the water column. all organisms need phosphates, so this is paradise for any organism. if the system has fresh LR, then it will be a race to the phosphates between the algae and the bacteria. because of all of the available phosphates both of these organisms can just grow like crazy until the free phosphates have been used up. as the phosphates are used up they are deposited on the substrate in a nice layer. this is where the cyano come in. they grown where they nutrients are, this is helpful to us because it gives us something to siphon. removing the cyano will remove the phosphates in its biomass. what we are waiting to happen to finally bring the "uglies" to an end is for the phosphate laden material to either be removed or sunk somewhere that is unavailable to the algae and bacteria. in all systems it works the same. in a BB system the free phosphates get bound up by the bacteria then fall to the bottom as bacterial flock, where it can be siphoned away or removed by the skimmer. even in a BB system it takes a while for the free phosphates to show up as something WE can see. until we can see it there is not really anything we can do. in a sand system we are waiting for the critters and bacteria to start populating the sand bed. the bacteria start to process the phosphates. in the process they wiggle the sand grains around causing the dead bacteria to fall further into the sand bed. the sand critters just help to speed this up since they are moving more of the grains around. eventually all of the free phosphates are sunk into the sand bed and the system is now only processing the phosphates that are added by feeding and things dying. an equilibrium has been achieved, for now.

i say flux because calcium carbonate binds phosphates. the bacteria are always trying to remove it and the calcium carbonate is always tying to bind it. so there is always a give and take going on here.

G~