Non CO2, Discus and improvement


Lifetime Members
Lifetime Member
Feb 12, 2006
Westchester, NY
Greetings all

I have lurked on this site for a long time and finally feel I am ready for some brutal advice. Be cruel to be kind. What I have enjoyed about this forum is they diversity in opinions - one size does not fit all. For now I am in the non CO2 camp and will persist with this. I do not want maximum growth but healthy plants and fish. I run some 8 tanks with two being the main focused and discussed below. The results are extremely different.

The 75G
Over the past year I have been experimenting with two new aspects - planted tanks and discus, among others. My current pride and joy is a 75g with 5 Altum Angels (approx 10 months old) with a school of 60 cardinals and 2pr of dwarf apistos. There are also ottos, a few cory (leftovers from another experiment) and the 6 dwarf loaches (eliminate snails). I have usually had about a doz of so Amano shrimp but for some reason in the past few weeks I have been losing them at some crazy rate - and I have no understanding why (I have added another 30 in the process) . For the plants I used ecocomplete as a substrate, and use Tropica master grow for micro.
On the macro side I do not fertilize at all.
Lights are 4 x 65, of which I use only 130w for 12 hours. I have stayed away from CO2 and yet the plants are doing well, with minor algae growth. Plants include hairgrass, dwarf hairgrass, echinodorus uruguanis (still small, in fact not growing much), a few crypt. wendti and as foreground dwarf sag and swords. Taiwan moss is doing great on the driftwood. Over the past few weeks the taiwan moss is showing a fair amount of hair algae growth. No shrimp to eat them.
Other indicators and equipment
Filtartion - 2 x Eheim 2028
Temp 81
Ph 6.8
WC -once a week 60 - 70%
Nitrates about 8 every WC
kh and Gh - 4
Feedings 2 x per day - Froz BW and pellets or flakes

My 180g, which is the main showpiece remains a challenge - plants and fish. Fish are currently 13 wild discus (approx 4 to 7"). I have only been keeping discus for a year and have found them an absolute pleasure. About three months ago I developed a intestinal disease issue and in the process have lost 4 of my original stock. I finally believe I have sorted that issue out. Other inhabitants include a school of rummy nose tetra (35), 5 clown loaches (soon to be removed), 12 ottos, very healthy Amano shrimp, three plecos and a some apistos.
For some reason on the planted side I cannot get the balance. Plant lists is as follows - Cryt balansae, crypt wendti (tropica and green), crypt pygmea, (recentlt added and wilted within 4 days),annubias nana, petite, hastifolia, frazeri and lanceleota. I am adding some anubias heterophylla, and more nana and petite nana this week. There is some moss (attached to some driftwood - this keeps dying off (turned a horrible mass of brown) and dwarf sag and dwarf swords (look rather poor vs the 75G). Based upon advice regarding the discus, I opted for the standard silica sand. It ensures that the waste remains on the surface, yet the plants do not do well in my opinion.
Here I have had little growth, annubias leaves yellow or or develop black spots, dwarf sag and swords look wilted, moss dies. Glass is constantly developing green spot algae and I always seem to have a green hue in the water. Driftwood has some BBA. Lighting is a total of 4 x 95, of which I am using 2 x 95 for 10 hours/day. There has been some improvement in the algae since I reduced the lighting from 11hrs.
ISSUES- plants not looking great, some algae, water clarity not fantastic (at time it looks like an LA smog storm with bits floating about)

Other parameters and equipment
Eheim wet dry 2229 plus eheim 2028
Added a 1200 maxijet a week ago (clarity of water has improved)
ph 6.8
temp 84
WC - 2 x week 75% (last week I have reduced it to 50% (water clarity up - was this the factor?)
No C02
Nitrates negligible
Phosphates negligible
Add TMG every second day
Feedings 2 x per day (Froz BW and pellets or flakes)

At this stage I need to make some changes to improve the conditions. My thoughts include the following

- use a substrate e.g eco complete for the rooted plants
- less WC (how much and how often)
- add some macro nutrients when doing WC

I would appreciate opinions regarding the above proposed changes and the timing of the changes. I think this would be an interesting experiment and hence I am loathe to make all the changes at once.

Thanks in advance

Tom Barr

Staff member
Jan 23, 2005
For the 75 Gallon:

I'd suggest adding some Excel here and there as needed for algae control.
Also, adding some K+, say K2SO4 would be wise. About 3/4 of teaspoon after each WC. Bend the rflectors out if possible so the spread of the Pc lights at 130 w is better targeting the plants. On fro 10 hours, and if the plants are looking good, add some Excel and add the full bank for 1-2 hours in the middle of the day.
You might raise the temp 2 degrees.
Feed some live red worms, live brine etc 2-3x a week(same for the 180 gal).

Use Excel sparingly. It'll cost more otherwise.


Get some EC if you like that color, Flourite etc otherwise of ADA AS.
Your choice there.
Discus need to be fed metrodianzol added to their foods often due to breeder's and wild caughts being fed those damn live tubifix and black worms.
Some breeders are good about it, many are not. But you should treat them with the food for several days/weeks till you are sure.

Unless you start feeding the live worms(not the red earthworms as I suggested) you should not have issues further.

Same as the other tank, add some K2SO4(1.5 teaspoons after each water change). TMG about the suggested amounts for both tanks, 2-3x a week.

Set up an automatic water changer, you'll save a lot of $, time and effort in doing so and they are relatively easy to add.

You can do more frequent water changes and reduce of eliminate the algae entirely if you do this and set it to do daily or 3-4x a week water changes.

You'll still need some fert additions, but like feeding the fish, it's easy then.
Excel can be added as well sparingly.

You might get a 4 liter jug of Excel.

But the cost of CO2 system is about 3 of those..........note: you can run two tanks with CO2 from one CO2 gas tank and regulator BTW if you were not aware........

Maintain the low light and add CO2 will make things do much better. You'd dose the following and it's not any more work than what you do now except you'll be able to garden more and have less algae:


KNO3 2x week: 1/2 teaspoon
KH2PO4 2x a week 1/8 teaspoon
TMG: 15 mls 2-3x a week

180: Double the above.

Automatic water changer: takes care of that.
Add a carbon filter before the water is added back(eg a 9 3/4" carbon filter cartiage canister from Home Depot etc with a good GAC filter cartiage)
The CO2 is simple and much easier to use with low light.

You can cross that bridge when you are ready.
I suggest non CO2/ non Excel methods when folks want to balance their plants and fish loads.

Bad idea generally for Discus/Altums due to high loading and feeding.
You can add a seperate refugium/plant filter is a sumpe etc on the outside of the tank to deal with the extra loading. But the main tenent of a successful long term plant tank without CO2/Excel is no water changes.

In order to do that successfully, you need to = the fish waste without plant deamnd.

But that's a trade off you are not willing to make. So you do the water changes and have more algae issues.

Since you are doing that work anyway, adding CO2 is a very simple solution and will allow you to do the gardening more effectively and get more out of the light you have.

100-150$ or so for the CO2 solution.
You can still use the Excel to help with the algae till it settles down.

Low O2 cause cause the murky water issue.
The wood etc will need to cure and the plants you have are rotting, not growing, that causes the O2 to drop a lot.

With active growing plants, then you have no such issues.

Tom Barr

Tom Barr


Lifetime Members
Lifetime Member
Feb 12, 2006
Westchester, NY
Tom, Thank you for taking the time, thought and energy to provide comprehensive detailed feedback. As a result of that I have a few additional questions as well as some items of curiosity

For the 75 Gallon:

I will do the following
add Excel
add some K+after each WC
bend the reflectors out
reduce lighting to 10 hours

Why would you suggest increasing the temp to say 84


You recommend a decent substrate as essential
Add K+ 1.5 tsp

Yes, I know the issue with the worms and after several months of treatment and temps for a few weeks in the low 90's all is well.

Not certain I followed this comment - "unless you start feeding the live worms(not the red earthworms as I suggested) you should not have issues further".

What was your reasoning for the live red worms, live brine etc 2-3x a week? Until recently I was feeding California Black Worms. This created a number of issues with the Discus - bad source hence parasites etc.

Plans in the distant future is to add the automatic water changer. This layout will be moved in about 12 months time.
I have been resisting CO2, but will likely take the plunge after test without but using K+ and substrate.

I follow you on the non CO2 and plant waste factor. In other words, not an option for the likes of many cichlids that are prone to high waste output. I would be interested in knowing if any others have been successful using non co2 with discus or angels.

Much appreciated and will keep you posted of results as I begin to change each element (SLOWLY), to assess impact.


Tom Barr

Staff member
Jan 23, 2005
Defining "Success" is rather arbitrary.
For many, no real algae problems, healthy fish etc, yes, plenty have had that.

Can you keep them together without issues, generally, yes, will the plants really grow and thrive and can you make a nice look etc? Yes, but some balancing and water changes are needed.
Depends on how much you feed, how big they are etc.

I focus much more on improving health and having a nicer and nicer set up no matter which method someone wants to do.
There is always room for improvement and growth.

Given the fish stock and water change issues, you need to go with either CO2 or Excel to have a high degree of success.

Tom Barr