[Raymond S.]

Due to my work schedual I usually can't do a 7 day week on WC.
I end up doing the water change at 8 or 9 days.
Just a little short of 50% also.
So my nitrates are a bit high by then. Those test cards are so easy to
read you know. I'd say 40 ish.
So can I substitute K2SO4 for the KNO3 in my ferts ?
Since this tank has few plants(yet) I only use half of the KNO3 and
actually I have already been using half KNO3 and half K2SO4 for that.
On "and I am dosing for" on the calculator, I use the EI Low Light/Weekly.
But on the KNO3 part only I do only half and substituted as above.

 

[jedimasterben]

Is it causing issues? If not, I would keep on keeping on.

 

[redant]

What substrate do you have in the tank ?? Some substrates give out nitrates. ..

 

[plantbrain]

Just use say 1/3 EI instead of 1/2 if there's not much plant biomass.

This assumes............ there's an issue other than a silly uncalibrated test kit.

 

[Raymond S.]

The sub is this gravel under a small amount of Flourite. Just what I had left over from a previous use.
http://www.plantedtank.net/forums/picture.php?albumid=14281&pictureid=52570
When I first do a water change and before I add my ferts, the nitrate test shows a very light orange tint to none at all. Just before the WC it's getting a slight red tint.
I have one otto and about four Least Killi fish in there but about 60 pre adult RCS
along/w about four adult ones. A 10g tank BTW
One odd thing is that my RCS do just fine till they berry. They often die at that time.
I put about 7-8 adults in there and now have 3 or 4. There is no other obvious problem.

 

[jrman83]

Wonder why your nitrates climb that high with so light of stock? Sounds like you overfeed quite a bit. Shrimp add so little. I have about 500 in a 20g and barely read any nitrates.

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[Raymond S.]

Wonder why your nitrates climb that high with so light of stock? Sounds like you overfeed quite a bit. Shrimp add so little. I have about 500 in a 20g and barely read any nitrates.

Sent with my Samsung S4 via Tapatalk

No doubt you are correct on this issue. I know I overfeed. Likely should cut back some and perhaps skip at least one day a week.
I never have any food left in there but it takes 3-4 hrs to go.
I have the idea that the bigger ones are crowding out the smaller ones and want there to be some left over after the large ones are through.
I finally was able to order a GH/KH test kit and a TDS meter.
You may rcall, this tank was switched from part Distilled to all tap water.
I have also changed from just over 20% WC to just over 45% as per
your suggestion.
I do put in a half of an algae waffer every other day. It's actually one of three things they run to most. Much more so than any other food I use.

 

[Diana]

a) Do Tom's suggestion of a bit less of each dose. That will slow the rise over the (long) week.
b) Yes, substitute K2SO4 instead of KNO3. I would dose perhaps half as much KNO3 each time, and make up the difference with K2SO4. While the formula is not exact, it is close enough for a straight swap of these two materials.