Return/Skimmer Pump

[GaryP]

another Q....

ive been told thaht using bio-balls causes high nnitrAte in a SW setup... is this true? if so, what should i use for filter media instead of bio-balls?

Yes and no. Are nitrates created by bacterial action in the bioballs? Yes. Is it supposed to be formed by bacterial action in the bioballs? Yes again. Is the source of high nitrates in an aquarium due to bioballs? No! That's pretty much the reefer version of an old wive's tale.

Bacteria form what is called biofilms on the bioballs where organics, ammonia and nitrite are converted into nitrates. Those same biofilms are formed on live rock, live sand, plumbing, inside skimmers, on the glass, etc. Basically anywhere there is a suitable substrate. I've never seen anyone suggest taking out LR as a solution for high nitrates, but the same logic would apply.

The reason for high nitrates is not the biofilms producing nitrates. Rather it's the lack of a suitable environment for the bacteria that process nitrate in the final step of the nitrogen cycle into nitrogen gas (denitrification). Denitrification takes place in low oxygen areas such as in a deep sand bed and to a lesser extent in the deep pores of live rock. Now we have the sulfur reactor that provides another technology for processing of nitrates but that still relies on providing a low oxygen environment for these type of bacteria to grow.

The folks that are advocates of running bare bottom or thin sand bed rely on another strategy. They try to remove the organic waste in a very efficient skimmer before it enters the nitrogen cycle as ammonia. I'm not sure what happens to the ammonia being excreted directly by the fish in a BB system. No one has ever been able to explain that part of it to me.

HTH

[Flobex]

ok thanks for all the info everyone!

sooo... what shoud i do about thhe very hifh flow rate? the skimmers flow, probably, shouldnt make any difference, because it will all be in the sump... right?

[matt]

I'm not sure if running the output from the skimmer to the tank is a good idea. If its a beckett, you will have microbubbles like crazy.

I can't speak for this particular skimmer, but the beckett skimmers that I've made do not release microbubbles into the tank when they're set up right. This is also true for most well made beckett skimmers (I'm sure Pete's is good) as long as they're run by the right pump and adjusted well.

But, you can't feed the skimmer from the tank overflow, if that's what you're asking. You need to have a sump, and you feed the skimmer from a pump connected to the sump, and drain the skimmer right back into the sump. You should use a separate return and skimmer pump; it's MUCH easier to keep the skimmer adjusted. If you're talking about a 29 gallon tank, unless your sump is about 50 gallons, running a mag 12 in your sump will create a lot of heat. A beckett skimmer of any size is really too big for a 29 gallon tank, but you'll have no problem keeping your water clean! Since Pete is making it for you, make sure you tell him what size tank you have and ask him about how to set it up. If it were me, I'd consider buying a nice external skimmer pump that runs cool like a pan world 100px (or even 50px if Pete can make you a really small beckett skimmer) and run your skimmer external; you probably won't want to run it 24/7.

[GaryP]

Good point Matt. I hadn't even thought about the heat issue, but it would definitely be a problem with that size tank.

[Flobex]

ok... well the thing is, he already started making the skimmemr before the givew away... so it isa what it is... i will llook for external pumps for both the skimmer and the return then... so whatt woud you recomend for an external return pump?

[Flobex]

ok, i have another question... for feeeding the tank, i know i need to get food dispersed for corals, and fish, and invers... so i had an idea, to make a box, and put a powerhead in it, with holes in one ennd of theh box, then i can put the food in the box, turn on the power head, and the food is dispersed everywhere... is this a good idea? or willl i need so many divers foods, that it wont work?

[hobogato]

not necessary. thaw and mix all your food in some RO water or tank water in a little tupperware container. once it is all thawed and mixed up, just pour it into the tank in an area of high flow, and it will spread all over the tank.

[Flobex]

ok awesome, thank you.

so for pumps, im thinking, as suggested earlier, the pan world 100px, for the skimmer, and a pan world 50px for the return. how does this sound?