Undergravel filters...please advise

[traceellamints]

Hi everyone,
I am new to this board and would like to ask my first question....first of possibly many!
We have an undergravel filter in our 45 gallon with powerheads working in the reverse flow, an Emperor 400, 35 lbs. of live rock, and a protein skimmer. We are tearing the tank down to move it to a new location to make room for our new 90 gallon. During this move, we are thinking about removing the undergravel, since we have other filtration. I would prefer to have the tank w/o the undergravel, which was recommended to us by our LFS when we purchased the tank. The ammonia/nitrites are 0, and the nitrate is 25 and coming down...the tank has only been running for two months. We have a Coral Beauty Angelfish, 3 Tomato Clowns, a turbo snail and 4 scarlet hermit crabs, all doing well.
What are your opinions about removing the undergravel? I appreciate all your advice.
Thanks,
Tracy

 

[sebae0]

imo and i think others too, it would be advisable to remove it.
add more liverock and get goog water movement in the tank, and possibly add a deep sand bed to your 90 and that is all the filtration you will need.

 

[aarone]

UGF's are horrible. Ammonia and nitrate traps.
aaron

 

[traceellamints]

Thanks for your advice....
And I agree.....with all the other filtration we have, I didn't see that the undergravel was doing a whole lot. We plan to get more live rock in the future for this tank.
Our 90 gallon is going to have as much cured live rock as we can afford to get. Right now, we've got about 75 lbs for it as a base for the coral.
We are using live sand over a layer of Florida crushed coral, aragonite formula...
Is crushed coral okay?
Thanks,
Tracy

 

[thomas712]

Definatly remove that UGF and you will have much less trouble down the road. Let me give you a few reasons why you should remove it.
This is my standard answer to the Undergravel filter:
As for undergravel filters, I've been through this, won't go through it again. Why?
1. Frequent water changes to try to get the ditrus and nitrates out.
2. If you put live rock on it you will build up more dead ditrus spots that will pump out more nitrates in you system. This just makes them simply non reef compatible. They were meant for a crushed coral bottom and are no good with sand.
3. You run the risk of Carbon dioxide poisoning that builds up underneath.
4. Although it can help with the bioload it is only low bio load friendly.
5. With what can seep out from underneath the algea blooms can be spectacular leading to what is called New Tank Syndrome even if you think your tank is seasoned, and if you do not vaccum well you will simply reintroduce the waste back into the water colum. This can reek havoc on your water chemistry and your PH.
6. Even though you use the best strongest powerheads on it, it will just pull the waste and ditrus down into the substrate traping it till it decays and fouls your water or waits to be removed by you and the vaccum tube. Much better to use sand and good water flow to keep the ditrus in suspension in the water to be removed by the protein skimmer or machanical filtraition.
7. No matter how you slice it the UGF is just a ditrus trap. If anything deserves the name nitrate factory it is the UGF.
Just my OPINION.
Since there are many other forms of filtration, almost all of them, are better. As was said lots of live rock and live sand, a refugium, wet/dry, all better than a UGF
Thomas
Welcome to the board

 

[oregonbud]

Welcome to the boards
Crushed coral is alright, but if you are going to use some live sand anyway I would suggest just doing a deep sand bed, it acts as a biofilter in addition to your LR. Not to mention construction of a DSB seeded with live sand is substantially lower then using crushed coral as your substrate.
Some advantages I feel of a DSB compared to crushed coral are
1.) No vaccuming.
2) Over time a sand bed actually acts as a natural filter that can lower your nitrate levels, where CC seems to trap nitrates and other waste.
3) Looks more natural in comparison to CC
Just my two cents

 

[michaeltx]

something else if you go live sand or snad of any kind mixing it with CC will cause some problems later down the road.
the CC is heavyier than the sand so over time it will move to the top of the mix and your back in the same boat with a CC base in the tank that will collect setirous and other things that in general will hinder your effort for good water quality.
BTW Welcome to the Board.
Mike

 

[traceellamints]

Thank you everyone for your welcomes and wisdom.
We have removed the UGF from the 45 gallon...
As for the CC, my hubby has already placed it in the 90 gallon tank I discovered......but we've only added 15 lbs of CC and 60 lbs of live sand. Our LFS recommended the CC for the needed calcium for corals.
Thanks,
Tracy

 

[lesleybird]

Well, I have a very unpopular opinion......I like crush coral because it looks good to me compared to my twenty five gallon quarintine tank that I but in the 1 to 2 mm. size crushed agronite where every time a fish poops you can notice it laying on the top of the sand bed. When I have the crushed coral mixed with some small shells (it came that way and I added extras for the hermits), I can't see the debris on the surface, and I have some white color with some purple coraline on the shells. I do not have an extreme nitrate problem like the others say can happen with crushed coral. I like it also because it is big enough not to be sucked up when you vacuum it. The agronite in the quarintine tank also seems to be just big enough not to get sucked up when vacuumed. I too am setting up a new ninety gallon in a week or two...Just got it this week. It was a special order from Oceanic with a reef-ready overflow box and holes drilled. I have decided to put a 3/4 inch layer of agronite 1 to 2mm. sand as a bottom layer and a 3/4 inch layer of my crushed coral on top. I am using the agronite sand because the people on here like it to improve water quality and I want to see what all the talk is about. I don't believe in deep sand beds for a tank with a lot of fish because they create so much waste that the deep sand bed can crash from it. They may be great in a lightly stocked reef tank that does not have many fish, and thus a low level of waste products put into the bed. I think that the thinner layer that I am talking about is deep enough for the worms in the sand, and not so deep that you cannot vacuum out a lot of the crud before your nitrates go too high.
I think that a deep sand bed or an undergravel bed can turn into a nitrate trap. When I was a teenager I had a twenty-nine gallon freshwater tank with the famous under gravel filter that has fallen out of favor...I had one of those cheap rod iron stands and could see all the fish waste just sitting under the filter plate forever! When I finally took it out it was a filthy mess!
Good luck with your new ninety gallon too.
The stocking list for my ninety gallon is as follows:
1 fairy wrasse
1 bicolor blenny
1 flame angel
1 sixline wrasse
1 damsel that may be replaced later with a small
butterfly fish (maybe not)
1 royal gamma
1 Majestic angelfish (queen of the tank)
3 scarlet skunk cleaner shrimp
a couple dozen micro hermits
about a dozen large snails
one brain coral,
a bunch of colorful mushrooms,
and a partridge in a pear tree!
Lesley

 

[traceellamints]

Well, Lesley, thanks! You've made me feel better about the crushed coral! I have known of others who have used it and did not mention nitrate problems. I agree with you about the deep sand bed, we had that in our 45 and our 29 freshwater and I didn't care for the way it just made a deeper area for debris and waste to accumulate that cannot be easily filtered out. We are going much thinner with our sand bed in the 90 gallon. We're certainly learning by much trial and error!
Tracy

 

[reefer44]

I think having a dsb made up of mostly live sand and a little crushed coral is the best.....but i also think it can be a detris trap if u don't have digging fish or inverts...for example i have a sand sifting star in my 55 gallon that moves all the detris to the top were the scavengers can get it, but what detris is left at the bottom layer of the same bacteria consumes it......also my tank is efficient enough that i have never made a water cahnge or vacummed before so i don't have a problem sucking up the sand...................also is ur tank going to be reef or fish only?

 

[jp0379]

Just to add my opinion, if you've ever seen a pic or actually went into the ocean, the bottom is sand. Sorta makes it a no-brainer, IMHO. More natural for the fish, so it can't be bad.

 

[dburr]

TraceEllaMints,
Where from CT are you? I am in Haddam. I vote for the DSB. But if it's not what you like, then I would do a thin layer.
BTW, we have a CARS (CT area reef soc.) meeting coming up on Nov. 1. If your interested e-mail me at dburr6525sbcglobal.net

 

[traceellamints]

dburr...
We are in Bristol, about 15 miles west of Hartford. Thanks for the info on the club and I may check into it.
Right now, we are sort of undecided about doing a full reef in the 90 gallon. Right now we have 4 Percula Clowns and one Swallow Tail (Black Spot) Angelfish, 4 hermits, and a Scooter Blenny and about 80 lbs of LR. We may just go fish only, if the reef takes as much care and maintenance as I've read about it, we don't have the time in our lifestyle and schedule for it. Besides the nitrates are a bit too high right now at 30 ppm I think for coral. Its at 30 also in our 45 gal. even with frequent water changes. If we can get the nitrate to go down, we may consider adding some coral.
As for the DSB, funny thing...after I posted, I found an article in "Tropical Fish Hobbyist" about DSB and all its benefits and have changed my view about it, but we're just going to leave the sand bed/CC in our 90 the way it is for the time being. The ratio of live sand to CC in our tank is about 6 to 1, so we're just going to see what happens.
Tracy