20H setup- confused

[AquaFilly]

Hello! I've been doing a ton of researching, but I feel so lost! I'm very sorry if this has been posted a million times already. Can't seem to find any solid information.

 

I've been thinking of setting up 20gal reef tank. I'd like to have a DSB and live rock as the filtration. What is a plenum? Should I put an undergravel filter in there? Still very confused on what kind of powerheads to get and where to place them. Also, if the DSB is 4 inches, I'll have 13 inches to place rocks and corals (later on). This seems a little shallow. Should I go with a 29gal (shaped like a 20, only taller)? I have a 24" hood that holds a 50/50 actinic blue light (from my old FOWLR tank) and 2 slots for 150w bulbs. Can I use this for corals?

 

So my questions are

Should I upgrade to a 29gal?

Should I use an undergravel filter?

What kind of powerheads should I use?

What kind of MHs should I put in there to grow most corals?

 

Thanks for the help!

[ninhsavestheday]

upgrading to 29 gal is really up too you. upgrading to 29 will be easier to maintain, giving you more room to make mistakes. it also provides more space for coral and such. upgrading to a 29 gal also means you need more LR and more lighting.

 

you dont need underground filtration for reefing. in reefing, filtration is taken care by the LR/LS, weekly water changes, and skimming. plus underground filtration is a pain and will just cause problems for your tank in the long run.

 

for powerheads i suggest you you use 2 of them and i recommend the maxijets.

 

2 150w would be enough for the a 20 gallon, but if you want to have SPS and maxims go with 2 175 MH.

 

heres an example of a good 20 G.

http://www.nano-reef.com/forums/showthread...&threadid=17063

[reefermadness]

The Jaubert (plenum) method is best left to experienced aquarists. You can cause far more problems "trying" this method if you don't know what you're doing. 2 x 150W might cause heat issues, so be careful and check it out before adding livestock.

[Jean-yus]

Undergravel filtration wouldnt do much, because all of the sand would just filter through the filter!

 

And 2x 150w MH is NOT NEEDED. I had a 40g reef with only a single 250w MH and it held ANYTHING, Birdsnest, Maxim Clams ALL sps, lps. NO problem. As for the spectrum I would suggest a 10k Metal Halide (10,000) and MAYBE an actinic for a visually better looking tank. I would put in two powerheads on opposite sids of the tank. I would also suggest a flow of 10-12 times (if you want fish) and 12-15 times if you want a fishless reef.

 

The bigger the tank, The easier it is to maintain, So if you want an "Easier" to take care of reef, Go for the 29. (For the 29 if you get that and go MH Get ONE 250w)

 

OK, this is kind of a pet peave of mine about nano's and this site, Its ok to use lots of light, but unless the tank is a 20L than 2 150w mh is not much use... Allot of people here give advice about lighting that is sometimes absurd.

 

"2 150w would be enough for the a 20 gallon, but if you want to have SPS and maxims go with 2 175 MH."

 

Sorry but IMHO this is bad info ninhsavestheday

 

Im not trying to pic a fight but IMO that is overdoing it...

 

So good luck with your tank.

[Smokin-Reefer]

Sorry but IMHO this is bad info ninhsavestheday

 

I agree, especially since I beleive the person is using a 20H which measures 24x12x16, not the 20L.

 

Slap a 150 DE or a175 SE and you'll be happy. Otherwise, get a 2x55 kit.

 

hth

[nalbar]

a plenum system is where the live sand is lifted off the bottom of the tank an inch or so. this allows water to get below it. the theory is that that water eases nitrite to nitrate converstion. if not done correctly it can cause dead spots which are a constant problem. best left to pros.

 

the deep sand bed is falling out of favor with many reefers. if you go the reek-central there are threads and threads of people removing thier DSB's. not properly maintained you end up being sand keepers and not water keepers (which is really what we are). forget the DSB. go with 2 inches of sand imo.

 

once again i will say it. get Tullock's book 'Natural Reef Aquariums'. considering you are going to spend a great deal of money on this tank 25 dollars for this book is a great investment. all your answers are in this book.

 

nalbar

[onthefly]

Well,

 

Nalbar finally answered the guys question: "what is a plenum?" However, one small correction, the plenum is specifically designed to create a low oxygen area (anoxic, hypoxic, anerobic...what ever word you want to use). This low O2 environment is where certain species of bacteria can use NO3 as a source of O2, releasing free (non-toxic) nitrogen bubbles. The species responsible for NO2 -> NO3 requires O2.

 

I've been running a plenum/DSB in my 45 for 5 years...no problems! No problems when the PH fell and disrupted the DSB. No problems when the sand sifters move the sand around. I always hear people talk about DSB's crashing.....I've never met anyone how has had one crash. The theoretical lifespan of a DSB set up is reported to be 5 years, but most people break them down before this (moving, rearranging, etc).

 

Here's a link to a LFS here in Portland. Woody (the owner) has a PhD and is a retired Chemist, he talks about most of the "misconceptions" about plenums: http://www.seahorse-nw.com/Aquarium_Setup.html

 

All that being said, a plenum in a nano is a waste of space! Keep up with w/c's and you'll never have a problem. I run a 3" DSB in my 5.5ga and have never registered NO3, even after my cycle. As evidence, I can see hundreds of bubbles in the sand bed. The trick to a good DSB is the grain size.

 

As for the lighting, if you have the hood....use it! Don't spend more cash to get a whole new setup! Get a couple of 150's and call it a day.

 

HTH