Tank Troubles


Junior Poster
Feb 13, 2007
Here are the problems I am encountering and hoping for help or guidance.
46 gallon bow front up and running 6-8 weeks. CF lighting 10 hours duration. One 96 watt bulb on for 10 hours, the second 96 watt bulb on for 2 hours for a noon day blast. ADA aqua soil substrate. Well water with a tap ph 6.8, KH 7degrees. Pressure C02 with a drop checker running in the green zone. I know it works as when I do water changes it will be in the blue for a period of time before retuning to green color. Magnum canister filter with ceramic bio spheres. I have installed a surface skimmer on the inlet side of the filter.

Here is the issues. From the start I have been EI dosing with Greg Watson dry ferts. Doing 50-70% water changes every week. The first 2 weeks the tank exploded with new growth. Did all pruning and cleaning prior to water change.

The last 3-4 weeks a major out break of hair algae. And now very limited growth on any plants. What new growth appears gets coverd with hair algae. Also there is a bronze to rusty color sediment that attaches to all leaves. This can easily be removed rubbing the leaves but returns within a day to 36 hours. I have been in contact with Greg Watson and he referred me to this area for big gun help.

My nitrates were well over the 40-60 ppm range while still doing major water changes at least weekly or every 3 days. I continue dosing CSM+B, magnesium sulfate, along with mono potassium phosphate. I have not added any potassium nitrate as my nitrates seem to hover in the 5-10 ppm range. The tank is not attractive to look at and the water never appears sharp and clear. It carries a yellow tint and am guessing from the tannins from the ADA substrate.

Very minor fish load: 3 ottos, 3 rainbows, 3 glow light tetras, 4 rasboras

Any and all help or suggestions are needed. I dont feel the plants are healthy enough to sustain a 3 day blackout to try to turn the algae around.

Thanks in advance for your help...Tracy


Lifetime Charter Member
Lifetime Member
Jan 24, 2005
Sacramento, CA
Stop testing for nitrates. Dose nitrates per EI. Nitrate test kits are not known for accuracy, and you are depending on one to determine that you don't need to dose one of the most important fertilizers? Where are your plants supposed to get nitrates?

Tom Barr

Staff member
Jan 23, 2005
Generally with ADA AS, you need to do more frequent water changes in the start up phase, about 1-2 months.

2-3x a week water changes, Amano does them every other day for the first month.
Good CO2 etc.

Even if you do not have any plant uptake, the max range for a 46 gallon using EI at 1/2 teaspoon 2-3x week of KNO3 is not going to exceed 60ppm ever, that assumes no uptake, no denitrification etc.

Some NO3 can come from the Aqua soil however.

Still, 60-80% water changes should knock the NO3 way down, but that same dilution.
So if you change out 50%, the 40-60ppm should now read 20-30ppm and so on.

If not, you have a test kit issue.

Likewise, doing a 75% water change should drop the ranges into the 10-20ppm range assuming the tap is NO3 free.

It does not seem like the there is enough CO2. Hair algae + slowed/stopped growth.

There are enough nutrients, water changes etc, good substrate, light........
Not much else left.

You have a lot of light, too much in my opinion.
2 x 39W T5's would have been a much better option.
More than enough to grow any scape.

I'd add more CO2 and see.
Add some Excel to beat the algae back, do a 1-3 day blackout with daily changes and full excel dosing each day after the water change.

Increase CO2 and watch.
Pay close attention to cO2 over a day cycle, see if it varies, takes awhile to turn on etc

Tom Barr