live rock and UG filter???

[val]

I have a 125 gallon fish only marine aquarium established about 4 months now. I have a coral beauty, a flame angel, 5 yellowfin blue damsels, 4 4-striped damsels, 3 ocellais clowns, 2 tomato clowns, 1 high fin (banggai) cardinal, a yellow tang, 2 firefish gobies, 2 green chromis, 2 chocolate chip sea stars and 1 brittle star. All fish are (currently) small. I have an Eheim 2028 filter with appropriate substrate and chemipure in the top basket, a wet-dry Eheim 2229, an Aquaclear 110 filter with charcoal, a submariner UV sterilizer, a Red Sea deluxe protein skimmer, a Magnum 350 and Magnum H.O.T. (both with micron cartridges that I change weekly), an undergravel filter with 3 strong powerheads (crushed coral gravel), and a phosban phoshate reactor. After all this was established, I read about and decided to add some live rock just for the tang and angels to have algae to nibble on (and for the additional filtration). I don't intend to grow a reef tank or corals.
My question is: Can I (please?) just add live rock to the aquarium with some additional lighting? (How much lighting?) I really don't understand the reason some aquarists say you can't use live rock with a UG filter or wet dry filter. Please enlighten me. Also, please let me know what changes I would need to make to successfully add live rock.
I really enjoy and appreciate your website, and would be grateful for any advice you can give me. Thanks, Val

 

[winyfrog]

You will be fine to add live rock, you will need to make sure that it is fully cycled before putting it into your tank. Live rock should be in all aquarium systems. As far as your angels and tang giving them something to nibble on its not the rock its the algae that grows in your tank that they will eat.

I would also suggest to you to remove that undergravel filter asap. The UG filter will cause you more maintenance issues such as needing to vacuum your substrate regularly which will remove beneficial bacterias as well as pods, and will harber nitrates and phosphates.

 

[Rcpilot]

There is nothing wrong with an undergravel filter if you just know how to take care of it.

You DO have to vacuum it frequently. Probably every 2 weeks in your situation. I'd vacuum out about 20 gallons every 2 weeks and replace with fresh saltwater mix.

EVERY type of aerobic bacteria filter will produce nitrates. It's the natural sequence of things. Ammonia gets broken down into nitrite. Nitrite gets broken down into nitrate. Thats a fact of nature. You can't have an aerobic bacteria colony without nitrates as the end result of that biological process.

BUT:
If you have some anaerobic bacteria in the system somewhere, you can break those nitrates down into harmless nitrogen gas. The nitrogen gas then bubbles out of the water at the surface. WHALLA !! the perfect biological filter!!

But, undergravel filters usually only have about 1--2" of gravel.
Q: Where can you get anerobic bacteria to grow in an oxygen rich environment like an undergravel filter? Don't those types of filters only support aerobic bacteria?
A: You can't. Only the aerobic bacteria will grow in the undergravel filter.

So, you're stuck with nitrates. Or you change a lot of water on a weekly or monthly basis. Right?

Nope.

Put the live rocks in there. There are all kinds of little nooks and crannies where oxygen rich water will never reach. THAT'S where the anerobic bacteria will grow and break down the nitrates into nitrogen gas.

In all reality, it's not practical for her to remove the undergravel filter now. It's an established tank full of fish. I don't think that Eheim wet/dry filter will provide enough aerobic filtration all by itself. Removing the aerobic bacteria bed in the undergravel filter will almost certainly cause a system crash.

You didn't mention your lighting system.

You need 4 watts of light per gallon of water to grow live rocks. Thats a MINIMUM. I've heard of people going up to 8 watts. So, make sure your using a metal halide or power compact lighting system. I'd have AT LEAST 500 watts of light on that tank and maybe as much as 750 watts. Some people might even put 1000 watts of light on that tank.

You can certainly just put the live rocks in the tank right now. Won't hurt a thing if they are fully cured out and ready.

I WOULD NOT buy uncured live rocks for that tank. It will cause a huge ammonia and nitrite spike and could kill some of your fish.

Get fully cured live rocks if you plan to just stick them in there.

It will help your biological filtration to have some live rocks in the tank. You could put 50 pounds in there and it would look like almost nothing.

Keep in mind that a "reef" tank with mostly rocks/invertebrates and very few actual fish will typically have 1.5--2 pounds of rock per gallon. If you wanted to set up a reef tank with a 125 gallon tank--then you'd be looking at purchasing between 175--300 pounds of rocks. Just an example. Big ole heavy rocks don't look like much when inside the tank. Seams a tank will swallow up 20 pounds of rock like a snack.

I've got right at 39 pounds of live rock in a 30g reef and it looks bare. I'm shooting for 60--75 pounds when I'm all finished stocking it.

 

[Bifferwine]

I disagree with RC on a couple things... Removing the undergravel filter at this point would not be a hassle. You have barely any live rock in there. Yes you have fish, and when you pull the UG filter up it will make the water cloudy for a bit, but the fish will be fine. It's much easier to do it now than after you add more live rock. I made the mistake of starting my tank with an UG filter, and removed it after a couple months when my tank was fully stocked. It's not a big deal to take out.

Second, if you do keep the UG filter and add more live rock, it will make it nearly impossible to keep the substrate clean and vacuumed. You will not be able to vacuum around or under the rocks, and this will most definitely lead to poor water quality problems that cannot be fixed without removal of the UG filter.

Lastly, I don't think you need 4 watts per gallon to keep live rock. The bacteria will grow in the rock regardless of lighting (most of the bacteria live in the crannies where there isn't any light anyways). If you want to keep corals or stuff like that, then yes you will need better lights, but for just live rock, you don't need special lights. Granted, you probably won't get much, if any, coralline growth on the rocks, but oh well, it's still better than without the rock.

 

[Rcpilot]

On the lighting:
I meant that it would take about 4 watts per gallon to grow the algea.

The original poster wants to add the live rocks so that the fish have a bit of algea to nibble on.

Sure, the rocks will support both types of bacteria colonies.

But will they actually grow algea without some decent lighting? I am not sure. I thought you needed pretty substantial light to grow the algea.

The rest of the stuff-- we'll have to agree to disagree. ;)

 

[HAWKS12thMAN]

have i seen this post before?

 

[reeffreak]

Honestly,I would remove the UG filter and the crush coral.If that means that the fish has to be in QT then so be it.Both of them are nitrate traps and shouldn't be use.I would replace it with a 2-3'' aragonite sand bed.I know I've said this a hundred times already but aragonite has superior buffering capacity,trace elements throughout the lifetime of a system.While CC loses those things in time.UG filter,CC,wet/dry can produce nitrates and live rock rock,sand bed can reduce nitrates.Do you see the conflict there.

Live rock doesn't need any special lighting-at least for the beneficial bacteria.If you want coralline algae then I would upgrade to at least PC's.As far as nuisance algae like hair algae,it grows just fine under NO florescents.I rather feed algae sheets to my fish then willingly let nuisance algae grow.