Upgrading

[Mr_Cool]

Ok, I might need some help here. I'm thinking of upgrading my 55 gal. I can't go too big, 'cause the wife would kill me. Anyway, I thought I'd keep the 55 as a sump/fuge, but it all depends on if I can get a deal on a whole setup. Here's my problem, though...

I have a deep sand bed (approx. 6 inches) and I don't know how I would transfer everything to the new tank. Wouldn't the denitrifying bacteria all die off in the move to the new tank? That it, I don't know how I would move it without oxygenating the whole sand bed. Anyone have any thoughts here?

The other thing is cycling. What do I do with my lifestock while the new tank is cycling? Whatever bacteria I have in the 55 certainly will not be enough to support, say a 90 gallon. And I know that the amount of bacteria is a function of the livestock. The more livestock you have, the more bacteria you will need. But, as the first increases, so will the latter. What I'm thinking is the liverock I'll need to add. (As I'm typing, I think I'm answering my some of own questions.) I guess I just add cured live rock, huh?

What about lights, though? Metal halides vs. T-5's? I probably can't go any bigger than 125 g, so what do you all think here? What am I looking at in cost? (Roughly.) Any thoughts would be greatly appreciated.

[carlinsa]

there is no such thing as too big........................

[GaryP]

1. Being oxygenated will not kill denitrifying bacteria.

2. Bacteria will reproduce quickly to compensate. This can happen within days. You will just go through a very brief cycling period.

3. Your problem is going to be from stiring up the nutrients trapped in your sand. Expect and plan for a algae bloom after moving to the new tank.

4. Lights depend on what you are planning on stocking your new tank with. SPS and clams - MH, anything else, fluorescents (VHO, PC or HO T-5s). MH may have a higher initial cost, but are cheaper when you consider the bulb replacement costs on a per watt basis.

[Mr_Cool]

I thought the denitrifying bacteria was anaerobic, though. (Well, not really ANaerobic. But, I know it doesn't get much.) I thought that the "risk" of a deep sand bed was that, if the lower levels were disturbed, the tank could crash pretty hard. No?!?

[NaCl_H2O]

Honestly, for the cost of a decent sump/fuge under the new 125, I wouldn't try to use the 55g. Leave it setup, drain enought to move it if needed then fill it back up. Setup the new system with new sand (if you want it), and live rock and let it cycle. Leave enough room for the rock from your old tank so you can move it over after cycling. Seed the new tank with sand from the old system. If you setup a fuge, use some of the old sand in the fuge when you move it over. While it is cycling, take old water from your water changes on the 55g and use it for part of the water change in the 125g.

When the new tank is cycled, pump water back and forth between the systems slowly to get the chemistry & temp exactly the same, then you don't need to aclimate the livestock - you already did!

That's how I did it, worked great!

Cost & lighting - Get a loan!

[Mr_Cool]

I was thinking of that, too. That way I can sell the whole 55 gal. set up. This way, I have a place for the livestock to stay. I didn't know what to do it, and I couldn't really leave it in the sump.

O'kay, now somebody hook me up with a great deal on a bigger tank!

[GaryP]

I thought the denitrifying bacteria was anaerobic, though. (Well, not really ANaerobic. But, I know it doesn't get much.) I thought that the "risk" of a deep sand bed was that, if the lower levels were disturbed, the tank could crash pretty hard. No?!?

They are anaerobic, but oxygen does not kill them. Otherwise any sand digging critter on the ocean floor would kill them. How did they get there in the first place? Were they teleported into the sand bed from an anaerobic environment in a laboratory somewhere? Actually though, they just shut down their metabolism and take up knitting until the proper anaerobic (or anoxic - low oxygen) environment is restored. Some of these guys are actually facultative, which means they can operate in low oxygen, or high oxygen environments. They have 2 sets of metabolitic pathways, but can only do the denitrification process in low oxygen conditions.

Steve's suggestiion about replacing the sand bed is a good one. A sand bed will not run indefinitely. Eventually there is enough buildup of silt and nutrients that it will crash. When I do my upgrade, I plan on saving some of the sand as a starter culture, and as a lower cost alternative to replacing it, I will kill the sand bed with fresh water and wash the heck out of it. I have done this in the past with pretty good results. A lot of phosphate gets trapped as calcium phosphate on the surface of the aragonite. I may think about doing some sort of mildly acidic wash of the sand to see if I can remove that. I need to see what would be available to do this with. Acid won't work because it would be quickly neutralized by the aragonite and I would just end up dissolving the sand. An acidic buffer might do the trick. I need to see what I can come up with to make an acid buffer. Hmmmm.... Where did I put that freshman chemistry book? Maybe a CO2 sparge.

[hobogato]

i have this one in the for sale forum

includes tank, stand, canopy, sump, continuous syphon overflow.

http://www.maast.org/index.php?name=...ic&t=14869

[Dozer]

talk to Polkster- he's a MAAST member. He sells lighting. After some initial problems with bad connections that were easily fixed my lights that I got from Polkster and 360Reef (the guy that used to sell them) have worked great. I'm happy with them and the pricing is very fair.