I mean the CO2 from the substrate/filter and fishes. But perhaps it doesn't add to much of CO2 anyway.

OIC! No problems from the fishes as long as the're not vastly overstocked. Should be no issues from the substrate either.

Generally I've found it good to have a gentle water current in my tanks. I think the nutrients are distributed better.

Ian

I have a non-CO2 45 gallon biotope tank. The substrate is soil from the river in question, covered with gravel from the river bed. Even the decorative wood came out of the mud. I stocked it with plants and fish from the catchment.

The tank is unheated, so mostly sits at 18 to 22 deg C. The lighting is two 36 Watt fluorescent tubes with a very efficient reflector.

I have been having some problems with algae. It consists of very fine green threads or very thin, almost transparent, films mainly trailing from the plants. I can get a lot of it out by twirling a satay stick through the water and entangling the algae, but that is obviously not going to get rid of it.

OK, Tom, can I suppress the algae with the right concentration of nitrate / phosphate / iron / whatever else? What do I test for, and what are the target values?

I think you have enough nutrients, but need more plants, eg, floating plants, at least 10-25% of the surface.

With non soil based substrates, I know what types of nutrients the tank needs and the rate.

NH4 is an issue with non CO2 soil based substrates.
Uprooting, leaking etc can cause issues. Stale soil after a few months also causes issues.

How old is the substrate and what types of plants/% planted is the tank?

Regards,
Tom Barr

The CO2 build up from night is used up in about 20-60 minutes when you turn of the lights.

Then the plants go into CO2 limited mode and stay there.
If you add this and a large water change( and/or expose the plants to air), often this will greatly increase a lot more than night time equilbration alone.
The amount from fish/bacteria is relatively small compared to a water change and the fish/bacteria and diffusion take place during the day as well, not just at night.

It's not an algae issue, it's a plant issue. Messing with the plant's adaptation will cause them to shut down and slow their growth until the environment stabilizes.

Plants do best in stable locations.
Hundreds of years even and this has been documented in FL springs. Clear constant temp water, ample light, same CO2(some are high CO2, some are low CO2, some medium, but all are fairly constant and have lots of plants.

Regards,
Tom Barr

The substrate is only about 2 months old. Most of the plants seem to be doing quite well, considering the transplant shock. In fact, some are pearling.

I suspect that I might not have enough plants. A lot of the foreground is still bare, as I wait for the many cuttings to grow and spread. It won't be long before the front half the soil area is covered. The back half is dominated by Myriophyllum crispatum and two different species of water ribbon with floating leaves. In terms of bio-mass, they are the biggest plants in there. I do not have any floating plants. I could put some azolla in there, but it's hard to get rid of later!

Last time I tested for ammonia, the test kit showed barely detectable levels. I'll check again.

What do you mean by uprooting and leaking? I'm not at all surprised that some of the newly planted fauna died or lost leaves, but could dead plant matter in the water upset the chemistry?

I'm not a low-tech, natural tank zealot. If you have any recommendations for water chemistry, I'll dose accordingly and taper off once the plants have grown enough to take care of it.

Thanks

Tom,

You say that adding Flourish Excel is an option if you want more growth. This would be a middle ground between Diana Walstead's system and the hight light, high co2 option. Would you have the same middle ground option dosing co2 at a lower level - say 10 to 20ppm? Or is there something about the Excel that makes this an option and not low co2?

Thanks, Bill

Thank you for this article.

I'm going to try your method. I have some tmg, will this be sufficient( plus
equilibrium) Or should I add something else with it?

If I start excel ( 60 gallons of water) tank what amount do you suggest.
( what would 7-1 mean for this tank.

Excel is not a Non CO2 method, I consider it part of a middle ground to CO2 enriched method, carbon enrichment if you will(rather than CO2 enriched).

You can and should do water changes if you use Excel.
If you have low light, then you can get away with longer water change intervals, say one every 4 weeks or so.

NH4 test kits will not show an algae bloom during or after the fact, only before, so you need to be looking for it before it happens, not after.

The substrate is only 2 months old and is getting close to stabilizing.
So the issues are not going to persist if you keep going and correct the algae, add more weds etc.

Do not worry what type, just add something that's easy to grow and phase them out later.

For dosing a non CO2/non Excel tank, I've given a rough guide, once a week dosing etc, a smidge of the ferts basically and a fish load.

Fish load alone can do it and adding a little KNO3 etc can really help over time.

Excel can use EI directly at about 1/4 dosing amounts 2x a week and likely be extended up to 2-4 weeks water changes. But if you have issues or want to keep things looking good and on top of it, do weekly water changes and see how well you can get the tank looking, then try backing off the water changes later if you wish.

So a 20 gal using excel would get:
2 w/gal light
Dose 1/8 teaspoon KNO3 1-2x a week
KH2PO4, 1/16th, 1-2x a week
Traces, 2mls 2x a week
SeaChem EQ 1/8th once a week
50% weekly water change
Dose 1.5-2x the rec dosing for Excel.


Etc

I started a 65 gallon tank 8/7/2005.Lighting is 116 watts.Substrate is 1/2 gravel and 1/2 flourite.It is loaded with plants growing at the rate for a non-co2 tank,
except for wisteria which grows a lot faster.
KH=8.9 GH=10.5. I add nitrate and phosphate and equilibrium weekly. Seldom is phosphate need.Everything is green no visible algae even on the glass. So it seems to be performing like Tom suggests.
I have many Anubia plants one of which has yellow around the edges of the leaf.
I added 1/4 tsp of TMG which seems to have helped a lot.( once a week for two weeks) I am considering using TMG more often. If so what is a safe amount? If I do include TMG in the dosing would it be okay to continue adding nitrate, phosphate and equil.

Thanks in advance for your help.