Help with Gregg Watson Ferts - Fertilizing

johnst65 · 10-20-2005, 07:47 PM

I just went over to the GW Ferts and now I have a hair algee issue.
MY tank is a 75 gallon all glss tank with a single corner overflow and a 18 gallon sump. The tank has about 3 inches of sand for substrate and C02 injection.

Light 2 x 96 watt PCs 10 hours per day
C02 4 bubbles per second approx
Plant load is heavy
Temp is 82

Fish
2 Blue Diamond Discus
6 SAEs
2 Corey Cats
1 Yellow Pleco

Day 1
75% Water Change
KNO3: ¾ tsp
K2SO4: ½ tsp
KH2PO4: 1/8 tsp

Day 2
CSM+B: ½ tsp
(No water change)

Day 3
KNO3: ¾ tsp
K2SO4: ½ tsp
KH2PO4: 1/8 tsp
(No water change)

Day 4
CSM+B: ½ tsp
(No water change)

Day 5
KNO3: ¾ tsp
K2SO4: ½ tsp
KH2PO4: 1/8 tsp
(No water change)

Day 6
CSM+B: ½ tsp
(No water change)

Day 7
Nothing

Any help you can give me would be helpful

Laith · 10-20-2005, 11:55 PM

Welcome to APC!

I would guess that you don't have enough CO2 in the tank.

You may be losing a lot of CO2 through the sump unless it's covered tight. So 4bps won't mean much. How are your plants doing? are they pearling during the photoperiod?

Plants need nutrients in the following order: Light, Carbon (CO2), macros and micros. Adding lots of macros without enough CO2 is not beneficial to the plants...

johnst65 · 10-21-2005, 04:30 AM

Thanks i'll up the C02 today

wannabescaper · 10-21-2005, 04:42 AM

Any idea what the co2 levels are? pH/KH?

johnst65 · 10-22-2005, 11:18 AM

The C02 increase did the trick

plantbrain · 10-22-2005, 01:15 PM

If you have issues in the future, always look at CO2. Then look at it again.
If plants do well for a couple of days after a water change, often the CO2 is to blame.

Your dosing is a bit rich, I'd back off the K2SO4 and also a lilttle less KNO3.
It's not likely you need that much given the tank as a whole.

Regards,
Tom Barr