Dosing question

[Thever]

I have a 10 gallon w/ 7 various size plants of helferi, along w/ a 'sheet' of riccia, it has about 40w on for 10 hours a day. I do diy co2 and struggle to keep nitrates up. I can add 12ml of kno3(which should give me about 6ppm nitrates) It seems close, but in less than 24 hours its gone.

Question is...should I dose everyday to help get those levels up? The plants arent the healthiest looking as of right now, and I just got over a bout w/ green water and dont want to shoot myself in the foot by overdoing it with things. Thanks!

 

[gzeiger]

Are there fish in the tank (ie are you adding fish food)?

You can safely go a lot higher than 6 ppm nitrate. Even with the most sensitive fish there seems to be a consensus that 40 ppm is safe, and some species will tolerate significantly more than that (not recommended though).

Nitrate is not the only important nutrient for your plants though. You're supplying potassium, but not phosphate, and depending what's in your fish food you're probably short of some micronutrients too. Plants need a whole lot of things like iron, boron, magnesium, sulfate, zinc, copper, manganese, calcium, and more, in tiny amounts that you couldn't readily test for (and some like copper are harmful to fish in larger amounts). These things generally are present in your tap water, although "trace" fertilizers are available to provide iron and a few other things. I recommend Flourish Trace if you think this is necessary.

I would recommend that you read this article on fertilizing aquariums: The Estimative Index of Dosing, or No Need for Test Kits - Aquarium Plants - Barr Report

 

[Thever]

I forgot to add that my phosphates are high already, and I do have a trace fert that I dose.
What I can dose is-
KNO3- 1ml per 5 gallons raises NO3 by 1 and K by .63mg/l
KH2PO4 - 1ml per 5 raises PO4 by .5mg/l
K2SO4 - 1 ml per 5 raises K by 1mg/l
CaC12 - 1ml per 5 raises CA by 1mg/l
Trace - Iron + micros - 2 ml per 5


It just seems odd that I cant keep the nitrates up. I dont stock any fish, just 5 shrimp which I have never fed,but I plan on getting 10 to 12 more in the near future.

 

[Purrbox]

You have practically no bioload and a descent amount of light of the aquarium, it makes perfect sense that you aren't able to keep your Nitrate levels up with so little dosing. I'd bump your dosing upto at least 10ppm, and probably even 20ppm. At the lower level you'll probably need to keep up with daily dosing, while with the higher dose you may be able to back off to dosing every other day.

 

[Thever]

Thanks, thats what I was thinking too, but needed some more input on it. Is there a rule of thumb regarding shrimp in regard to bioload? Like how many shrimp does it take for a decent contribution?

Kevin

 

[Purrbox]

For smaller shrimp like RCS, you can easily have a colony of 100-200 with adults, juveniles, and babies in a 10 gallon. So you're probably looking at 10-20 shrimp to equal about a slim bodied 1" fish.

 

[Thever]

Really? Sheesh! Guess I cant rely on them too much to help reduce my dosing.

 

[gzeiger]

Fish size is really a rough thumb rule. What really determines the bioload is how much you're feeding. Very few multicellular animals (some corals, and mostly only by symboisis with algae) can produce their own biologically available nitrogen. If you're not feeding the shrimp they are just eating plant debris or algae from the tank, which was going to become plant food anyway. If you don't feed them anything, their contribution to the nitrate level in the tank will be zero.