[xsavior]

I have just set up a 38 gallon marine tank with an undergravel filter, it is currently regular flow. I am about to add live stock as it is cycling well, but I was wondering if live sand (besides just the bacteria) is possible in a tank using undergravel filtration. Would reverse flow work better. I know that there are many more advanced methods, but this one is what i'm familar with in fresh water, and i hope it will work. thanks alot.

[dagnir]

I would say no. Most of your standard UG filters have slots that are to large and the sand will fall through. Is this a reef or a fish only?

What ever you have done and had success with in fresh water should go out the window when dealing with marine life. About the only things which are the same are the fact that you are dealing with water and living things and that the water needs to stay within the tolerance of those living things. Lighting, water movement, and all aspects of water quality in marine systems are a world apart from fresh water. The systems are by no means very difficult to keep but saltwater is its own entity. My recommendation is to get a good book, something from TFH's new microcosm series for example. Because the basis for success is knowledge, and there is going to be a lot of money and time put into even a small system, not to mention a few helpless creatures lives at stake. Its pointless to waste the money but wrong to lose life through ignorance. The tanks are beautiful to have and a joy to keep but only if the time is taken to do it right. I would recomend to read, then read, and read even more on what you are attempting. Good luck and there is more help in these forums than you could dream of.

[blue]

WELCOME TO REEFLAND

The undergravel filter is no help in salt water its going to do more harm then good so id take it out now while you can so you dont give up because of algea problems and nitrates and what not down the road. If you want to keep fish only i suggest you get one of the emperor bio wheel filters made by marineland and a skimmer such as a prism or bac-pack or even a aqua-c remora skimmer. If you are keeping fish only i would go with crused coral over sand. If you want fish and maybe corals later id say go with 1-1,5 pounds of LR per gallon and one of the recomended skimmers above you dont need the bio filter then because the live rock will be you bio filter i would also add a power head or two. For fish and rock you fresh water lights will do with some diffrent bulbs of courses such as 50/50 bulb. If you want to keep corals all you will need to do is get some more lighting such as VHO's or PC's or Metalhalide. and with rhe fish and live rock or a reef system you sould use a DSB or deep sand bed of about 4 inches this helps reduce nitrates. I know there are a lot of things i probably left out but like xsavior said read read and read some more. O know you asked only about filters but i thought id throw this in and help you out and normally your LFS is going to tell you about things you dont need so come check with us befor you buy again WELCOME TO REEFLAND ask all the questions you want we can help

BLUE

[xsavior]

I have several books on salt water tanks and I'm finishing up on a degree in Marine biology. I don't want anyone to think i just jumped into this expensive and time consuming "hobby" with no back ground. This is (on a small scale) what I'm dedicating my life too. I have a very good understanding of both fresh and saltwater aquariums and their HUGE differences. However, I have never put together a saltwater tank. Myself and my wife (also a student of marine biology) have spent hours recently talking to our local fish store owner who has been setting up and maintaining both large and small salt water aquariums for years.He told us this was the best set up but he isn't the most progressively thinking guy. It's been difficult to decide exactly what to do because every book and person we talk to has a slightly different opinion. Yours is also very much appreciated.

[Bughead]

Most of us have discovered that you can get a lot of misinformation from fish stores (LFS), and that this hobby has become a lot more expensive than it needs to be because of all the wrong stuff we're told. When I started 3 years ago, wet/dry systems were all the rage. But now it seems that the deep sand bed (DSB) and live rock (LR) is the most efficient and care free system. i've been using this system for 1 1/2 years now, and it's not only less expensive to set up, but it's much easier to maintain and my water quality remains pristine. You need a sump to make this work properly.

This is kool to have a marine biologist on the board. Hope you stay with us. What's your specialty area?

I'm in total agreement about the under gravel filter. Nix it. Another popular system several years ago was the plenum. It apparently works well, but the DSB is simpler, efficient and less likely to crash. (I've heard some horror stories about plenum crashes).

[deano]

My .02 My first marine aquarium run for 2 years with a UGF.
So! yes a UGF system will work in a Marine aquarium, as long as the sand particals are large enough not to fall though or plug the cracks of the UGF. I find meny, not all, LFS are years behind the current trends and a UGF system in a modern marine aquarium is consider old news. The big deal now a days in marine aguariums is NNR (natural Nitrate reduction Bob Goemans) The problem with a using a UGF with the flow either reversed or drown though is that it will do nothing to remove nitrates. Due to the fact that nitrates are converted to nitrogen gas by aerobic bacteria. This bacteria will die if oxygen is present. So as you can see by allowing flow though the UGF you will not grow the aerobic bacteria needed to consume nitrates. The other problem with the UGF is that over time detritus will build up in the SB and will need to be cleaned regulerly or it will cause a increase in nitrates because the dying or decaying matter in the SB will have to be consumed by the bacteria that performs the nitrogen cycle.

Remember the Nitrogen cycle!
fish waste or detritus=ammonia=nitrites=nitrates.
but heres where the nitrogen cycle ends. Keep in mind what goes in our little glass box must come out in one form or another. Unfortunitaly our aquariums do not have the amount of water or biodeversity of the ocean to do this for us.

Some are advicates of DSBs to perform NNR. A 5" SB will allow the lower section of the SB to go aerobic thus coverting nitrates into nitrogen gas. Myself, not a fan of the DSB, find that a well balanced system utilizing a LR, max 2" SB, Skimmer, refugium containing macroalgae, sump, coil denitrator and a eye on keeping your fish bioload low will maintain low nitrates. With little effort from me.

Are nitrates a problem in our aquarium? How much is to much? I don't know but I do know the Ocean is 0 in most places. I strive to duplicate my aquariums enviroment to the Ocean as best I can.

[dagnir]

I forgot to welcome you in my last post so Welcome A UG filter has been a main stay for so many years it is hard to get away from it for a lot of people. In your tank this is what I would recommend.

Fish Only:

A form of mechanical and chemical filter. Canister or Surface its your preferance. But be careful of the amount of Biological in it, more aerobic bacteria means more nitrate.

A good skimmer. Because it isnt just for reef tanks. Removing those proteins before they are broken down can help a great deal.

I would also recommend a Deep Sand Bed around 4 or 5 inches with good live rock something like cured fiji because of its biological filtering. The live rock will also provide food for alot of grazing fish in the tank.

A good turnover rate in the tank. I would recommend Maxi Jet because they are reliable and quite. Go for about 300 - 400 gph total.

Lighting isnt a big deal a brighter light in the higher kelvin ratings will show of the fish well. But balance the look and go from there.

Reef:

In your size tank scratch the mechanical and chem except for occasional carbon. Same live rock and live sand. Same skimmer. Same turnover rate you could even bump it up a little. And intense lighting. VHO, PC or Metal Halides choose depending on the type of corals.

Both are fun to do and in reality not much different as far as setup. In your tank you could probibly do a very nice small invert and fish tank keeping filter feeders like feather duster worms and the like. And not have to invest in expensive lighting. Be careful of over loading with live stock. A good cleanup crew like snails (nassarius, astrea, cerith), crabs and shrimp (scarlet hermits, mythrix, cleaner shrimp, coral banded shrimp) and star fish (brittle stars, serpent stars, linkia) are all very beneficial in any tank, reef or fish only, just as long as there is a good sand bed and good live rock, and no predater fishes.

Sorry for the lenght of the post but good luck and keep this thread goin with more questions.

[Bughead]

Just a little clarification. When Deano says the lower 5" of the sandbed goes aerobic, he meant anaerobic--without oxygen. Nitrates are converted to nitrogenus gas by anaerobic, oxygenless bacteria. I know this is what he meant, i'm just correcting his typing error.

[SPasse]

Xsavior,

Here are some good reference articles on how DSBs work.

http://www.rshimek.com/reef/sediment.htm

http://www.reefs.org/library/talklog...ek_090698.html

http://www.animalnetwork.com/fish2/a.../1/default.asp

Forcing water through a DSB via either forward or reverse flow would not be conducive to the faunal, bacterial or chemical processes that make a DSB work.

Besides, I doubt that you could force much water through the 4 to 6” fine particle substrate that you use in a DSB.

Regards,

Scott

[xsavior]

thanks very much for all of the advice, unfortunately, this is the set up that we have now, and we're trying to make the best of it. I should have mentioned that we also have two whisper 30s in addition to the two powerheads that are running the UG. I understand that the nitrates can be a problem, but RO water changes regulary should deal with that right? So we have alot of circulation, we would like to do a mixed tank, and i understand that the anaerobic bacteria will not develop, but live rock would still help right? And if we get some live rock going and then in a few months just turn off th UG, add a sump with miracle mud and some macro algae, perhaps with some live sand seeders, would that work to any degree if we added some fine sand to our current bed?

BTW what i'd like to do with my degree is to focus on shark sensory systems, as well as to continue diving in all parts of the world

[Bughead]

Sorry to say this, but a lot of filtration and frequent water changes won't keep the nitrates down once the tank begins to mature, at around 6 months. The best way to deal with it is to go with your next plan of action, the sump with a nice refugium and lots and lots of macro algae to gobble up the 'trates.

If I were you, I wouldn't even go with the UGF right now either. I kept a 40 gal tank going nicely for over 18 months with just two whisper filters, a bit of live rock and a 2" sandbed. Even though it was my caulerpa tank I had it overstocked with fish and I over fed, but never had a nitrate problem.

I think your filtration and circulation is fine. Don't bother with the UGF.

Oh, and welcome to the board.

[xsavior]

Now we just have to figure out how to return the UGF with out hurting our LFS's feelings We're going to run the tank with out the UGF, keep the whispers and PH's for circulation, and get alittle live rock to gradually colonize our tufa (which is going to be the main part of the rack work) We'll get the living sand bed going with the live rock, and get some of the little critters that help it out (it'll be cool to get little tiny starfish and such), and after a few months we'll get the sump with the caulerpa going (btw this may be stupid, but how do you get the water going to the sump (I'm hoping you're not going to say canisters) Every one talks about sumps like they are a given, but i've never seen it wrtten out in plain english. This is what i wanted to do in the first place (LR LSB) but i figured it would be too expensive, but hopefully this will be an economical way to start. I know it will be slow going but would a couple of pounds of LR be enough to get the rest of it going? Keep in mind that it is not yet the main method of filtration. Thanks for all the response

[xsavior]

ok, so if we already have about an inch of crushed coral on the bed, how would you suggest suplementing the rest of the living sand bed strata? Miracle mud? Powder sugar grade stuff? finely crushed argonite? and has anyone had expierience in the past with setting up living sand and rock from seeding like this?

[xsavior]

DUH!! you use the siphon to get the water down there, and a canister to get the water back, right? Is there an standard to calculate how fast the siphon pulls, and how fast the return has there fore to be? and does anyone have pics of their sumps?

[deano]

Bughead thanks for catching the anaerobic mistake for me.

[deano]

xsavior

You will not regret removng the UGF now instead of later like I did. Plus the Idea of just shutting it of later is not a very good one either due to the fact that once the detritus builds up under it you will have a huge nitrate and algae problem

Their a several ways to get water from the main tank to the sump, syphon is one (as you stated), over flow box or have the tank drilled for a overflow. At this point and to keep from starting all over heres how I handle the exact same problem. I'v use this for about 5years now and never got water on the floor.

Heres a diagram of a simple sump/refugium that I use on my 45 gal tank. I run a 4" DSB in this sump/ref. with some macroalgae. I used a 20 gal AG tank, $20 I think, a maxi jet 1000 for return, piece of plexi glass silconed into the 20gal tank for a bulk head. and a syphon to bring the water down to the sump. To keep all the water in the tank or sump/ref. not on the floor. I made sure that my syphon was within a
1 1/2" from the main tanks water suface. This way if the pump quits the water will syphon about 2 gal from the main tank than quit. As for the sump, putting the bulk head on one end and controling the flow with a valve on the the return and feed line, to keep the water level in the return part of the sump low, plus leaving the water level a inche below the top of the sump you will have enough room in the sump to hold any water draining from the main tank if the pump quites. Now for the reason you need the bulk head in the sump. This will only hold about a gal of water. If the syphon stops and the pump keeps pumping this water will fill the main tank but once the back side of the bulkhead emptys you will not over fill the main tank. I used the maxi jet because this pump is tough as nail and can handle running out of water for some time. My maxi jet I use was used in one of my FW tanks and is about 15 years old. This method takes a little messing with at first but once you get it dialed in it works like a charm. Of course the best method is utilizing a built in overflow.

PS:
I agree 100% with dagnir IMO a skimmer is one of the most important filters of the marine tank. Skimmerless is fine for some but for starters I would use one. If down the road you dicide you don't need it, most don't, you can remove it.

[deano]

ok, so if we already have about an inch of crushed coral on the bed, how would you suggest suplementing the rest of the living sand bed strata? Miracle mud? Powder sugar grade stuff? finely crushed argonite? and has anyone had expierience in the past with setting up living sand and rock from seeding like this?

Like I said I'm not a big fan of the DSB, at less not in my main tank. But if you are going to run a DSB in the main tank do some research on how to properly maintain one. If not they can bite you. I think Scott gave some links to info here.

As for the sand to use most use fine grade aragonite reef sand 1-2mm or if you live in the southeast part of the US you might be able to find Southdown sand. For more info on this product just do a search on this board. I will not go into it because it has been cover very well already. The search will find you threads that will answer all your questions here. Just type in Southdown, you can read for a week.

You should be able to put the fine sand over the top of the CC. Its possiable dumping 3-4" of sand on top of what you have now will kill some of the fauna. If your concerned you could add the new sand a rate of 1-2" a week till the desired depth is reached (this can be very messy though) or you could remove some of the current CC and put it on top of the fine sand just hide it behind the rocks on the back side of the tank. This should help seed the new sand. Plus your LR will also help seed the sand.

I also would like to welcome you to the Salty World! I'm new to this board but not new to the hobby. I'v made all the costly mistakes a human can make in this hobby. So anytime I can help someone else not make them "I'm in" Boards like this one helped me out of the hell holes I'v been into, not my LFS. So heres where I get my advice and share when I fill I can contribute.

[Bughead]

deano's explaination of the sump construction is pretty good. I started out with sump-less systems and was almost clueless about what a sump was and how it worked. Luckily we have a couple of LFSs that have display tanks with sumps and a fellow reefer invited us to his home to see how he set up his system. Seeing the thing in action is worth a thousand drawings and explanations to me--with my female brain.

As far as the DSB, it doesn't really matter where it's at as long as it's somewhere within the tank system. Personally, I like the way it looks in the main tank, although at first I thought it was ugly.

You mention crushed coral....now we can get into the whole area of sand. I gotta go right now, so somebody please jump in here with the rundown on aroganite vs CC, particle size, etc.

[xsavior]

btw is a refugium the same thing as a sump? Alright, now the bulk head, how does that work? do you perforate it? do you leave an inch clearance in the bottom, i gues i'm just not sure how the water gets from the main part of the tank to the other side of the bulk headhow fast a flow id you need with the 45 gal, and how much was the pump?

[xsavior]

btw is a refugium the same thing as a sump? Alright, now the bulk head, how does that work? do you perforate it? do you leave an inch clearance in the bottom, i gues i'm just not sure how the water gets from the main part of the tank to the other side of the bulk headhow fast a flow id you need with the 45 gal, and how much was the pump?
And back to the sand/liverock seeding thing, any one have any comments about that?