[Mako]

How often should I perform partial water changes on a low tech tank? I read only a few times a year, but I also read weekly. Which is best?

 

[TAF CAF]

It mostly depends on your water stats. If your plants are sucking up your nitrate, and all your other stats are okay, then you don't have to do frequent changes. I only change water in my 55g when I am setting up a new tank and want to use some of the aged water in the 55.

However, if your nitrate builds up or you have other probems with your water stats, you will need to change it more frequently.

 

[wood]

Change 25% of your water once a week and you wont be disappointed.

-Ryan

 

[Mako]

This is why I say I'm getting conflicting information, and I really need to know what's best so I can make some decisions in what direction I want to go.

Not for a properly set up non CO2 tank, it's actually easy(no water changes), but you must follow the guidelines, some folks read only the no water changes and some plants parts......they do not read the details which are critical.

Same with reef tanks, it amazes me and then they complain and say ahhh......so and so does it and why don't I have success with 5 plants and a 12 oscars or 10 lbs of live rock and 20 fish?

You need to really read things and do it right from the very start, they do this added effort(actually it's called reading the directions/manual etc before setting it up.......something many folks seem to have a lot of trouble with then pay the price........... that's the real lazy part.........) and can really reap a lot of benefit from it.

Being smart and working a little at the start to be lazy and reduce labor in the long run is wise.

Being lazy to avoid work alone or when trying to understand something is just lazy..............
Do not be cheap and not add enough plants/live rock from day one.

That applies to every and anyone.
Balanced fish loads, lots of herbivores, adding chemical removers for NH4 and organics etc in the start up phase, proper substrate, filter, etc.

I have 3 years on a marine tank, 4 on a non CO2 planted tank without any water changes.

Regards,
Tom Barr

 

[TAF CAF]

I suppose you prove your own point with the quote.

Every tank is different and will need a water change scheme of it's own. We can only tell you what we do.

 

[yoko]

I think that when it really comes down to it, it is all a matter of time and observation/ experience.

I don't think there is any "equation" , even to the most "ideal" set-up.

Even if you followed a Step-by-Step, there are so many factors that effect your outcome and no one has the exact same set-up.

I think a lot of people learn best by trial and error.

They eventually learn what works best for them and their budget/ schedule/ lifestyle.

If you were to set up your tank, perform water tests, observe the fish and the plants and continue to do this for the next 2-4 weeks, this should give you a good idea of your water parameters and from there you can do water changes accordingly.

If by week 3 you notice something off in your test, perform water change.

My best advice is to keep a good eye on your fish and plants and go from there.
Have fun, good luck:smile:

 

[toffee]

Hope this helps:

Originally Posted by 2wheelsx2
Thanks, Tom, but I am still not understanding why water changes would encourage algae?

I have two bristlenose plecos and 1 bulldog pleco, and a Gibbey pleco and none of them touch the stuff. SAE's will eat BBA? The black bushy stuff?

Don't ask why, just do it if you want the issue resolved.

SAE's will definitely nibble and prevent it in non CO2 tanks if you stop those water changes.

Less work if your solution, seems weird, but it does work.

You can still do the no water changes and bomb with Excel also.

The water change flushes the tank with lots of fresh CO2 rich tap water.
This one time flux once a week favors the Algae, BBA likes slightly higher CO2ppms, around 5-10ppm seem optimal and flowing water.

Excel is a biocide at higher concentrations, like H2O2.
It's active ingredient is used for a number of things for this purpose.

It's selective and can kills fish and plants at higher levels and some species like Egeria.

I'm trying to get a test set up for it's selective usage for killing Egeria weeds but leaving the native species alone and enhancing their growth.

BBA will generally never grow in a non CO2 planted tank that gets no water changes, top off only.

Some folks have taken to changing their water late at night and then hopefully degased water come morning. Often it takes a little longer than 12 hours for that to occur, so they often still end up with BBA.

This is speculation, but it does make sense in the context of what is known about BBA and the method works and the hypothesis is supported by the many observations from folks over the years.

Something about what changes influences BBA, I know it's not the N, P, K, Traces, GH/KH, lighting(as long as it's suitable for a non CO2 plant tank).

So not too many things are left........
While some like to say I speculate, they do not offer up a better alternative hypothesis.

Plant density is one, you need a good well planted tank for this to work.
You also need a source of nutrients for the plants in a non CO2 tank, fish waste and soil/nutrient rich substrate can typically supply perhaps 80-100% of the nutrients, some plants will certainly benefit from KNO3/KH2PO4/Gh/Traces once a week or two or if you want to use inert substrates/lighter fish loads or the substrate is depeleted.

I've done both and they both are simple and easy to care for.
Dosing once a week, no water changes?
Is that(adding 2-3 things weekly) as hard as feeding the fish daily?
No.

So you can do the entire non CO2 method with inert substrate and not a ounce of soil, but you have to make sure you add things to the water column once a week.

When you add Excel, 1-2x a week and more is required, CO2 gas, 2-3x a week is required and so on.

Anything that increases the demand for nutrients must be added in the same relative proportion, so more light=> more CO2= more nutrients and so on......

Same thing, different direction: less light=> less CO2=> less nutrients.

Regards,
Tom Barr