Where's the line on partials?

[Krugar]

Just something I've noticed:

There seems to be 3 major periods for water changes in SW tanks.

<= 20G is IMHO is a nano & gets changed weekly.

>= 180 is a "Large Tank" & I think the average there is monthly.


Somewhere inbetween is a bi-weekly schedule.

Are there actual "lines" there or is it just a matter of learning when your tank needs a partial?

Cheers!

[Fisherman]

i change my water in my 20g once a month.. i have a oversized skimmer that keeps most stuff in check..

[Krugar]

I'm looking too see if there's a rule of thumb.

Did you start off doing a monthly partial on your 20, or did you fall into that over time? How did you decide on a month? Was it testing or arbitrary?

Cheers!

[Fisherman]

Well truth be told.. when i first started the tank.. i decided every 20th of each month is my maint day.. i used to test but stopped along time ago lol..

i don't believe you need to do to many Water changes.. Corals and some other filter feeders enjoy somewhat dirty water..

aswell my 20g on has 2 little clown fish in the tank lol.. and softies and LPS..

and my protein skimmer is rated up to 75g.. says 100g but i think they always add more then the skimmers can chew..

[Krugar]

I've got to see your set up :)

The skimmer is in a sump?

I think you're way into the exception side though.. I'd be interested in a poll, but to get the info I needed I'd have to have 2 questions:

What's your tanksize & how often do you do a partial.

Might be an interesting corraltion...

Cheers!

[Fisherman]

My tank is 24x12x16
lighting is 2x 65w PC 1 10k & 1 actinic
25# live rock
2.5" crushed coral substrate
tank sits at 79
not a clue on parimeters.. except salt.. and ph..

ph 8.3
salinity 1.025

my tank is a xenia growing farm lol... it grows like nuts in my tank..

[mickyfin]

I heard xenia grows well in tanks with more phosphate levels then what an SPS reef might shoot for...

I grow Xenia like crazy too in my 30 gal, and hair algae grows well too :-P

[mickyfin]

As to water changes, there really is no set forumla...

For example if you have a lagoonal type reef, you may be able to get away with less than stellar water quality.

If you run an extremely clean tank, you may be able to get away with supplimentaiton to replace trace elements.

Really it's personal and depending on the type of corals you keep, I've read about people on RC who haven't changed water in 3-6 YEARS.

I wouldn't advise it though!

[Fisherman]

3-6 years yikes.. i do it once a month. and im happy with that..

i also do 25% a pop..

[Krugar]

I didn't expect there to be a formula, but am I out to lunch with my observation that it seems the smaller your tank the more fequent your water changes (on average)?

[mickyfin]

I would agree based on the following -

Since the goal is to keep STABLE params, and small tanks become unstable much more quickly, it makes sense to do more frequent water changes.

Also smaller tanks tend to be have more heavy bioload-to-water ratios then bigger tanks. Hence they need water changes sooner.

Am I Making sense?

[Fisherman]

well once a month works for me..

Im actually thinking of selling the setup.. everything goes.. stand/PC lights 130w/tank/2 powerheads/heater/prism skimmer. oh yeah yellow star polyps lol.. there growing on the glass.. Some live rock stuff with yellow polyps and mushrooms on them... moving rest to my main tank..

if you know anyone who want a full functioning setup let me know..
no cycling required..


Reason being i would prefer to have one tank.. 1 maint.
Nanos are great but im getting lazy lol.. and the tank is to nice just to tear down lol..

thats also why i do it once a month

[Krugar]

Absolutely & I'm just making conversation.

I'd also add to it that people with larger tanks have more equipment.

A weekly 20% partial replaces everything in the tank & keeps me from having to dose anything but alk occasionally. I don't have to worry about a sump etc. but I'm talking about 2 gallons of water. Coffee cup bailing & a pail over 15 minutes.

I suspect a weekly 20% on a 500G tank would accomplish the same & you may not need to skim but now we're talking about 100G a week. That's going to add up to alot more than a huge skimmer, sump, dosing chemicals etc. etc. very quickly and changing 100G sounds like a lot more work than 2G.

Likely a fair assumption the coffee cup is used to hold coffee & possibly bailey's.

So either extreme is pretty "straight" forward to figure guess at.

I'm just curious where the crossing point typically is.

I doubt we'll find out though with out a survey. Maybe when the free time fairy comes by I'll do up some php code for Ivan so he can have a "multi-diminsional" survey.

Cheers!

[Fisherman]

i bet you people with a 500G would change water bi monthly or more..

[Flame*Angel]

I'll bet that people who do few or no water changes don't feed their tanks much. I suspect that there are quite a few anexoric tanks out there.

[Toutouche]

Originally posted by mickyfin
I heard xenia grows well in tanks with more phosphate levels then what an SPS reef might shoot for...

I grow Xenia like crazy too in my 30 gal, and hair algae grows well too :-P

Well, you're on the right track but it's not just the phosphates but moreso various nutrients in general ( and yes phosphates can be grouped into this too) because Xenia grows naturally in turbid waters.
A few other corals that also grow in turbid waters are most plate corals, Goniopora, GOB's, etc...

[Krugar]

GOB?

[Toutouche]

Green open brain ( the Jello-ee type).