W/D vs Sump

[Wolf3101]

I run completely submerged media for my sump and I disagree with you whole heartidly there. For one, the media in mine is basically 'extra'. I am confident I have enough uptake by plants as well as more surface area in the tank than I need.

But you dont see any advantages to a submerged sump compared to canister? How about maintaining constant water level in the tank, getting lots of equipment out of the tank (heaters, probes, reactors, etc. - most can be made inline, but thats additional work and cost) providing easy access to add stuff to the water (meds, ferts) or take water samples without getting into the tank, extra oxygenation due to overflows, a lot more water volume in the system, easy to implement auto top offs or auto water change, etc... there are many advantages to a sump. I dont run wet/dry since I dont want to off gas any more co2 than I need to since I run pressurized co2 into the tank. But I really like the sump setup and probably will have a sump on any future tank I can.

And 'crowded' depends on the setup. Some (like loaches for example) like to be crowded. Its pretty common to see them piled up and I am sure they would appreciate as many of their kind as your system could support.

By crouded I was refuring to the japanese style of fishkeeping....and when I said I saw no advantage I was refuring to the differance between the true wet/dry and the sumerged sump as it pertained to the question. The point was that submerged systems REMOVE O2 from the water while Wet/dry systems ADD O2 to the water. Like I said....properly set up....any and all of these systems will work very well. Each has its own advantages and uses. My comments where in the context of the question asked only....

 

[Hadrian]

What about nitrate? doesn't a submerged system have more anaerobic bacteria to get rid f nitrate as well as amonia and nitrite? I have heard this somewhere, is it true and dioes that give a submerged system an advantage??

 

[amehel0]

from my understanding of how amonia gets converted to nitrite and nitrite to nitrate is that when converting to nitrates they use oxygen and a lot of it which is the main reason why under gravel filters arent good because they are in the water column they use all the oxygen. the great thing about wet dry is that by allowing alot more air into the media area you can get alot of oxygen going to the media and have alott of oxygen in the main tank( by replenishing with an air stone. once there is no oxygen arobic bacteria start to die and are replaced with anarobic bacteria anarobic bacteria convert nitrates to nitrogen gas which leaves the system and into the atmosphere. this coindcides with how live rock works . pockets of stagnant water within the porous rocks alow little flow and co2 which allows the best environment for anarobic bacteria. the way to get rid of nitrates within a freshwater system would be in my opinion either a sulphur denitrator or a freshwater refugium which would be a massive 300gallon tub filled with bioballz porous rocks. where only 100gph is pumped and added co2 so as to have oxygen levels next to nothing