Re: 50% too much?

[Thomas Barr <tcbiii at earthlink_net>]

> 50 % weekly water changes are far too much, especially with a planted tank
> You are asking for a nice bacterial bloom which will take weeks to clear.

I'm going to do some guessing.

Well, there is one way I do know that will work, maybe two. But it's related
to something else not so much the water change and should clear up in a few
days. What type of filter do you have on what sized tank etc?
Non filtered plant tanks will sometime get this(I have one running now).
I don't think it's bacteria though. I checked by running it through a UV a
few times. It's some non living colloidal precipitate. The UV would have
roasted it fast had it been any kind of bacteria or fungus. It lasted about
3-4 days with the UV going all the time. If it's alive, it's scary stuff:-)
Even if it has doubling times of 20 minutes, it could not have survived what
I did to it.
 
Your set up might be fine with this routine, great. Try and reproduce it
now. I think if you try a few more plant tanks w/CO2 enrichment and
different filter set ups, you will not find this to be true. A non CO2 tank
does not use water changes except perhaps once every 3-6months etc.
I do large biannual water changes on those tanks, roughly 50%. It doesn't
happen to them either.

If you use CO2, certainly larger water change will help a tank.
If you increased the bio filter section, got a larger filter, increased
current etc, I bet you'd no longer have the cloudiness.

I've tried to test everything and lower the plant growth way down, not do
water changes etc and I can get away with things like this also, but my
plants do much better if they get regular maintenance. It works if
things(nutrients) are put into the gravel, the gravel is deep, the light is
lower and the CO2 is high etc. But doing large water changes still helps
these same tanks also.

Let's hear about your filtration first.
I'm going to guess weak filter(or one that clogs fast) and has little no bio
section, lots of organics/fish and high light. Maybe DIY.

> 10 % 
> weekly/or 25 % monthly is more realistic.
> This apart from the bother of having to readjust your traces at such frequent
> intervals.
> Tony.

Trace levels drop off fast in the water column. Dosing every few days is a
good idea if you add traces to the water column. The traces are gone anyway
by the time the water change occurs(weekly or monthly). Some folks might
toss some out if they do it daily but I do it every 3 day myself. You are
welcome to test this to prove it to yourself. I already know what happens.
 
Folks that have algae problems and need to reset the tank also need large
water changes to get things back on track. 25% monthly is not going to solve
their issues.

Now take that another step:
If that has a large effect on algae reduction when there IS algae, it only
makes sense that if you do this BEFORE algae appears and cater to the
plant's nutrient needs, you will have even better success than waiting and
getting lucky on your balance. I can tell based on plant health and get away
with this but I know I will have better results if I just do the work than
trying to guess/test. It's just easier. I feel better knowing rather than
guessing. It's cool when you guess right but you also know it's a risk also.

The less the risk, the better. Algae insurance.

50% weekly water changes also works great for folks with reef tanks(no
supplements, CA++ additions etc, but cost a lot in salt but is perfect for
small little tanks in the 30 gallon or less sizes), fish only tanks and
Discus(they tend to be 2x a weekers).

60-75% reef tank water changes a week really does a great job but folks
would rather spend the $ for the high tech stuff, than good old water
changes. It really solves most of the problems that aquarist encounter if
they do this one simple thing. Folks will almost never have fish illness if
they do this also.

I'd look into "why" your tank clouds up. You can likely just keep things the
same since you are happy etc or you can fiddle with it and see why it does
what it's doing and at least you can go back to the original starting point.
But most folks are doing much larger changes, having healthy intense plant
growth and doing 50% weekly year after year after year. I've been doing that
routine for over 25 years, Salt, FW, plant etc.

Regards, 
Tom Barr