Help with choosing new filtration.

[Shark Bait]

I am currently using a wet/dry filter with a protien skimmer and I'm thinking of switching to an Eco-System. Is anyone using this system, I have seen it in use on a 180 gallon reef and they swear by it. Now the few things I'm not sure on is that you don't use a skimmer any more. Input would be great.

Link: http://www.aquadirect.com/store/customer/product.php?productid=368&cat=174&page=1

 

[clayswim]

I've never used an Eco-System before, so I can't really comment on that. You should, however, make some sort of change to get rid of your wet/dry. If you have plenty of live rock in your tank, it will eventually act as a great biological filter for your system. The change needs to be done slowly though. Little by little take the bio material out of the trickle chamber, over a period of several weeks though so your tank isn't shocked. Keep an eye on ammonia levels during this time to make sure you're not removing it too fast.

The reason why you want to change is because wet/dry filters will remove ammonia and nitrites fine, but they do nothing at all to remove nitrates. Live rock on the other hand will remove all three, leaving your tank mostly free of nitrogen toxins. How the rock does it is debatable, with nobody knowing for sure. It's obvious though that the rock won't remove nitrates out of the water column the same way it will ammonia. So if something else in the system creates the nitrates to begin with, like a wet/dry, the rock is unable to remove it.

Clayton

 

[mojoreef]

Clayton LR can reduce nitrate because it has an anaerobic zone (very low oxygen) whcih creates an enviroment for dentrifing bacteria which have the ability to reduce nitrates to denitrogen. the rest of your discription is dead on.

Shark bait a MM eco system set up operates closely to the same way a deep sand bed does. It creates differing enviroments for bacteia to populate. All of the bacteria with in the have nitches in reducing nitrogen based products. However the MM ecosystem does it a little different. The so called Miracle Mud creates the anaerobic zone because it is made up of very fine particles that go oxygen free quickly. this zone will reduce nitrate to gas. It uses bioballs to do the nitrifing process, which is to convert ammonia to nitrite and then nitrite to nitrates, the nitrate laiden water then passes over the MM and is denitrified. It is kind of a dis-jointed system but seems to work for some.

Pros: are that it is replace once a year I believe and thus reduces the risk of long term build up (something a dsb doesnt do).
although not as effective at processing nitrogen based products, it does do it.
cons: Not as effective at reducing nitrogen based products and will leach small amounts bak into the tank.
the make up of the MM itself has very high contents of Iron and quartz. both of which are nutrient and can feed algae and macro algae.


Hope it helps


Mike

 

[clayswim]

Hey Mike,
Yeah, the debate I was referring to is why the rock will remove nitrates created within itself, but apparently not nitrates in the water column. The assumption by many is that because of the "dead" environment the anaerobic bacteria live in, that the proximity of denitrification is important. Speed of nitrification also comes into play. Some people (not I ) still question if that's true though, that if the water is full of nitrates that the anaerobic zones should still feed on them. Obviously though, they don't to any great degree. Just thought I'd throw that out. By no means am I an expert on chemistry

Clayton

 

[mojoreef]

Ahhh I see Clayton. I didnt realize that was a debate. It is an interesting topic though. Denitrifing bacteria will get an ammount of nitrates out of the water column but not anywhere close to what they get from with in LR and LS. I think folks think of denitrifing bacteria as a static thing, only living with in anaerobic zones, when it reality they can live in fully oxygenated areas anywhere in the tank. When in those areas they fix oxygen instead of nitrates for respiration, but usually end up creating thier own anaerobic localized zone through the creation of biofilms.

An example: Piece of detritus lands on the bottom of the tank, As soon as the detritus is formed it is set upon by bacteria (both nitrifing and denitrifing) both strains will attack the detritus reducing it. Bacteria cant just jump on it and begin chewing on it, they have to liquify it in order to consum, so they excrete a number of biproducts that does this, these products form biofilms around the detritus in which the bacteria travel and live. These biofilms also transform the enviroment from aerobic to anaerobic. The dentrifing bacteria will continue to respire using oxygen until it runs out in that area and then begin to respire using nitrates in its place.

So you will get a bit that way, but nothing even close to what occurs in the depths of the anaerobic zones of LR and/or LS where the zones are more static and the creation of biofilms and other biproducts push the food directly to them.

Anyway just thought I would through that out.


Mike