me-n-my-fish
Here's 10 reasons to and 10 reasons not to.
Refugium:
PROS
1) Adds more water to your system - normally a good thing.
2) Provides a safe place away from predators for growth of copepods and other life.
3) Provides a place for growing macro algae for nutrient export.
4) If growing macro algae, and you either leave the regugium lighting on reverse photo-period ( at night ) or leave them on 24/7, it may help stabalize pH swings in your display tank.
5) Provides a place to grow algae for feeding some plant loving fish species.
6) Provides a food source for pod loving fish and invert species.
7) Many feel a refugium aids in controlling water chemistry parameters, allowing the tank to become more stable.
8) Some feel that by running an established refugium, that a protein skimmer is no longer necessary ( although this is somewhat debatable ).
9) Additional surface to air ratio may increase/decrease dissolved gasses in your main tank ( O2 and CO2 ).
10 ) Utilizing a DSB in the refugium may allow for denitrification of nitrate.
CONS
1) You have to buy the stuff to set it up.
2) You must tend to it as another small tank - meaning there is some general maintenance involved, havesting of macro algae now and then, and cleaning of some parts.
3) Space limitations - you must either go above tank gravity, under tank or place it somewhere else. Sometimes this can be tricky.
4) If something dies in the refugium, you must identify it and remove it asap, otherwise this can affect your main tank health.
5) More lights and pumps may lead to excessive heat concerns in your main tank.
6) Potential for leaks.
7) Macro algaes can go sexual, reproduce and you may find it growing in your main display tank.
8) If macro algae is not harvested and allowed to die off - it may add nitrates, phosphates and other undesirable compounds back into the water system.
9) If flowrate through the refugium is too low - can allow for stagnation and a great place for undesirable cynobacteria or other micro algaes to grow.
10) Some people find them to be unnecessary, and prefer to run a good protein skimmer instead.
Macro algae - Most folks will plant a variety of caulerpa - doing so will allow those species of algae that will do well under your water and lighting conditions to take off, and those that do not like your particular conditions to just die off.
Live sand or dead sand - either one is fine.
Live rock and a DSB is okay.
Something in the refugium for caulerpa to "attach" itself to works as well.
Keep thinking about setting one up me-n-my-fish.
I think they are a wonderful addition to the tank system, help the overall conditions of your tank, decrease the amount of cleaning and maintenance and let you learn how marine plants grow.
