Marine Maintainence :


Hopefully by the time you reach this stage, your tank will have cycled fully.
It may not actually be mature yet in terms of stability and being an eco-system,
but at this point, your livestock will have started being placed into your reef biotope.

Maintenance is a pretty important part of marine aquaria. Everyone has heard before that maintenance is so difficult,
and so on and so forth, but it doesn't have to be too painful, if you're patient and take things slowly.
Remember that in a marine tank, only disasters happen overnight. Good things take almost forever to happen!!!

Most of the maintenance relates to keeping your water quality parameters as close to perfect as possible.
Most of the common areas that are within our control will be covered here.

Test kits needed :

a) NH3 - ammonia
b) NO2 - nitrites
c) NO3 - nitrates
d) KH - carbonate hardness
e) Ca - calcium (more for hard corals)
f) PO4 - phosphates

This may seem to be a lot, but in actual fact, other than (e), you're supposed to use all these anyway
in freshwater tanks, but most people don't bother since they do weekly water changes.
If you're willing to do the same for your marine tank, it's possible that you may not need to test so often too.

1) Nitrogen cycle stability :
If you have been patient during the cycling period, then ammonia (NH3) and nitrites (NO2-) should both be zero.
Nitrates (NO3-) might be close to zero but not necessarily.

2) pH and KH level.
Our SW is generally kept at a pH range of between 8.0 and 8.3;
However, it can fluctuate between daylight and dark hours to a larger extent.
This happens because during the daylight cycle, photosynthesis occurs in corals and algae which
absorb CO2 from the tank, hence increasing the pH.
At night, the reverse happens and they release CO2 into the water, which causes the pH to drop.
This is one of the reasons why refugiums are sometimes used in a sump or in a hang-on-back filter.
These refugia normally contain macroalgae and have a light that runs either on a reverse daylight cycle from the tank,
or even on a 24-hour basis. This will prevent the pH from dropping too much.

KH or carbonate hardness performs 2 functions :
a) Enables hard corals, coraline algae to form their skeletons in conjunction with Calcium ions in the water.
If you just have high Ca, but low KH, it's not going to happen. Both must be be present in the correct proportions.

b) When maintained at 8 degrees or above, it will stabilise the pH, preventing it from swinging up or down too much.
This is a natural property of KH and you do not have to worry too much about how the chemistry works.
Just keep it between 8 to 15, and it will be fine. KH can be increased by adding powdered or liquid buffers.
But try never to increase the KH by more than 2 degrees per day.

3) Calcium level - this should be kept within 400ppm to 480ppm, if you have a reef tank with corals.
Even without corals, it will help the pretty pink and purple coraline algae to grow on your rocks.

Calcium can be increased/maintained in several ways :

a) Liquid additives usually containing saturated calcium chloride
- this is very concentrated, and you have to be very careful not to overdose,
or it will react with the KH in the water to form calcium carbonate,
and subsequently, BOTH calcium and KH levels will drop.

b) KW
- kalkwasser or saturated calcium hydroxide solution as mentioned
in the subtopic of handling evaporation under the temperature main topic.

c) Commercial 2-part ionic salts

d) Calcium reactor
- this is a cylinder containing aragonite or crushed corals.
CO2 is dissolved in the water to form carbonic acid which then dissolves the aragonite.
This will then increase BOTH Calcium AND KH levels for you.

e) KW reactor
- this is a device that simplifies (b) so you don't have to make fresh batches everyday,
but at the moment, these are quite expensive.

4) Phosphate (PO4-) control
- this is quite an important area to cover.

When PO4- levels are detectable in your water, you will usually encounter a green hairy algae outbreak of either Derbesia or Bryopsis.
Derbesia is like hair having long thin strands that cover everything. Bryopsis is fine featherlike which will also cover everything.
Sometimes you may not detect any PO4- in your water, but you still have hair algae growing on the rocks.
This happens normally because your tank does not have enough water flow, and detritus (powder-like broken-down waste matter or particles)
settles in the holes of the live rock. These detritus pockets contain PO4- that are absorbed by the algae and so you can't detect them in the water.
Just make sure you have enough current in your tank to keep the detritus off the rocks.
Alternatively just before you do a water change, you can always use a small power head and blow off the detritus on the rocks.

If PO4- are in your water, you can use PO4- absorbing resins or just change some water.
This is one of the reasons why you still need to change water even though your NO3- levels are zero.
KW (Kalkwasser) will also react with the PO4- in the water and can be removed using mechanical sponges.

As mentioned, it is important to change water even when your NO3- levels are zero.
This will remove PO4- for you, it will replenish trace elements and minerals,
push up the KH and Ca levels, remove other forms of organic wastes that have been missed by the protein skimmer and/or carbon.
Some people prefer to use PO4- absorbing resins and top-up trace element and mineral additives,
but water changes are usually cheaper, although a bit more tiring (especially if you have a 2000 gallon tank!!).

Algae control - The most commonly encountered algae is brown algae or diatoms.
These usually start growing on the glass, and sand, then the rocks.
Diatoms feed on silicates which are present in tap water,
so if you use distilled water or RO/DI (reverse osmosis / de-ionised) water, this will not occur.
However, diatoms are non-toxic, and many of the in-house larger zooplankton like copepods and amphipods actually feed on them.
Diatoms can be easily taken care of biologically by using certain animals like the algae blenny, Turbo, Astrea or Trochus snails.
Some bristletooth (tang family) will also eat them. If you put a handful of Trochus snails in your tank,
usually they will reproduce in your tank, and you can get new generations from there.
Of course you can also wipe the glass with a magnet or sponge

Green hair algae as covered above is caused by PO4- usually within LR pockets.
You can just pull them out, and this will actually remove PO4- from your system.
Some fish like tangs, rabbitfish and foxfaces will eat them, but usually only when the algae is still short.
Once they have reached more than 1" in length, most tangs won't touch them (too tough, I think).
The rabbitfish and foxface will still eat them unless they're VERY long.
In this case, you have to pull out most of it first, then the fish will help you finish off the rest, and prevent new ones from growing.

Cyanobacteria - red slime algae - this is probably the worst kind of algae you will encounter in your tank,
and is directly caused by very high NO3- levels, and usually indirectly by a change in lighting at the same time.
This algae will coat EVERYTHING in your tank except for the fish !!
There is no real cure for it, other than resetting up the tank.
It's always better and easier to prevent it by keeping your NO3- low.


Equipment maintenance

Clean the skimmer collection cup whenever you see anything more than 1 cm of dirty fluid collected.
Don't expect it to fill up to the top, it will not, since the dirt at the bottom of the cup will
get thicker and thicker thus preventing the foam from rising any further.

If your airstone skimmer is producing less foam, change the airstone.

If your venturi skimmer is producing less foam, squirt some hot water down the airline tubing
into the venturi valve to dissolve the salt deposits there.

Daily, just look at it and the organisms, making sure everything is open fine, and feeding well.
Remove any dead organisms ASAP. Make sure all pumps, filters (if any) and other accessories are all working.
Topup with FW or KW if your water level has dropped - do NOT wait a whole week to do this,
or your salinity and other parameters will be changing. Oh, and feed the organisms if necessary.

Weekly, test your NO3- levels until it reaches zero, then you can test monthly.
Also test your KH to ensure it is staying at 8 degrees or more.
If possible, change 10% of tank water, or whatever is necessary to keep NO3- under 20 ppm.

Monthly, test NO3-, KH, Ca++, PO4-.
Change 25-30% water if weekly changes have not been done.

Half-Yearly, clean your pumps and powerheads to make sure that the impellers are still spinning smoothly.
If you're using FL or PL lights, they should be changed at this point to ensure the intensity remains high. Otherwise, it will start to drop.

Yearly, change 10000K and 20000K MH bulbs as well as T4/T5 bulbs.

1.5 Yearly, change 6000K or 6500K MH bulbs.



Other than standard commercial fish food, you can also breed your own brine shrimp
and enrich them further using phytoplankton (not yeast!).
You can also blend your own seafood items with some spirulina or nori sheets (just don't let your mum/wife/GF know!).
This will provide some variety to your fish. Remember that tangs and other herbivores need more greens in their diet.
You can also feed live phytoplankton directly to your tank for
certain corals and for the featherduster worms, clams and other filter feeders.




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