General Fert Questions

1202 Views 9 Replies 5 Participants Last post by Wasserpest, Oct 3, 2016

SteveMcdermit

Discussion Starter · Sep 30, 2016

hello all,
i have recently conquered a bad spell of Black Beard Algae all dying off now, but during this phase i was completely cutting out nitrates and phosphates, which i think a lot of people would not have done, my question is i have never dosed phos or nit before and i have recently bought a few dry fertz; should i start dosing straight away as the black beards dying off or rather wait till its all gone and start dosing nitrate and phosphate?
another question i had was concerning my Ph-Kh-CO2 levels, ive been referring to the ph kh co2 chart to read how much co2 is in my tank, is this the best method for reading co2 levels and if not are there any other methods in doing so?
Ph roughly 7
Kh 5
nitrate and phosphate undetectable.

Save

1 - 10 of 10 Posts

Wasserpest

· #2 · Sep 30, 2016

Steve - welcome to the Planted Tank!

Assuming we are talking about a planted tank, if your NO3 and PO4 levels are undetectable, I would suggest to start dosing right away. Now remember that saying "a little bit goes a long way" and that one "more isn't always better". In that sense, I would at least initially keep an eye on the levels, to figure out how much fertilizer your tank eats (depends a lot on light levels and plant mass/health).

Also I am not clear whether you are dosing CO2. If not, there is no great need to measure it either. In that case, we are talking about low tech, and hopefully your lights levels will be appropriate for that.
If you do inject CO2, then yes, the pH/kH ratio is the easiest way to get an idea. Note that when you say "roughly" 7 for the pH it does make quite a difference whether it is 6.8, 7, or 7.2 (and would correspond with good/medium/low CO2 levels). So you'd either get a decent liquid pH measuring kit, or even better, an electronic pH tester.

See less See more

Save

IntotheWRX

· #3 · Sep 30, 2016

SteveMcdermit said:
hello all,
i have recently conquered a bad spell of Black Beard Algae all dying off now, but during this phase i was completely cutting out nitrates and phosphates, which i think a lot of people would not have done, my question is i have never dosed phos or nit before and i have recently bought a few dry fertz; should i start dosing straight away as the black beards dying off or rather wait till its all gone and start dosing nitrate and phosphate?
another question i had was concerning my Ph-Kh-CO2 levels, ive been referring to the ph kh co2 chart to read how much co2 is in my tank, is this the best method for reading co2 levels and if not are there any other methods in doing so?
Ph roughly 7
Kh 5
nitrate and phosphate undetectable.

I don't use any measuring devices for my CO2. Or even temperature (human finger is great for that) It pushes me to do trial and error and have a better understanding. The drop checker tool is a crutch for beginners. It's not always accurate and it wont help PUSH you to learn how to read CO2 otherwise.

I usually look at how the bubbles are dissolved into the tank's water. If the CO2 levels are low, the bubbles will dissolve, disappear faster. When my CO2 levels are higher, the CO2 bubbles will float around my tank longer before disappearing. Perhaps the water is more saturated with CO2.

I also look at my plants. I'm looking for pearling bubbles. When they pearl hard, the CO2 is good. If the pearling isn't going hard, then I don't have enough CO2

every bubble counter is different because it gives different bubble sizes. I use a spiral bubble counter and I measure the shape of the spiral. It shows me a frequency that the bubbles are coming out.

Practice pushing your CO2 levels around. Know your limits. Be conscious about it and eventually you'll learn a inner feeling of how much co2 is in the tank rather than relying on a color of a drop checker. in the end you wont need tools to measure, you can simply look at all the 100 factors you've been studying and be a pro and figure out. most people here will tell you to put your nose in the books and crutch yourself to a drop checker. trust your heart and have understanding.

See less See more

Save

SteveMcdermit

Discussion Starter · #4 · Sep 30, 2016

Thankyou all,
i do run injected CO2 and i will invest in buying a pH pen for future use, one last question is i want to start using Estimative Index for my method of dosing, should i start with a half dose and build up to a full dose overtime, or should i completely forget about doing that at this stage?
I guess ill start experimenting and play it by ear with the CO2 also within reason ofcourse. aha
Thanks for all the advice!

Save

Solcielo lawrencia

· #5 · Oct 1, 2016

CO2 does not need to be "good" for plants to pearl madly. The above photo shows Rotalas pearling at less than 15mg/L of CO2 under high light and very low nutrient levels. Plants can pearl just as much with <10mg/L of CO2.

As for dosing, a little goes a very long way. Depending on other parameters, 0.1mg/L of PO4 and 1mg/L of nitrate should be sufficient. The nitrate will probably be used up faster, depending on how much CO2 is available and plant health, so may need to be supplied more often if fish waste doesn't provide enough nitrogen from ammonium. Urea, ammonium, and nitrate are all sources of N and plants do have specific preferences for which ones they prefer and at certain ratios. Dosing nitrate alone is not the best way to provide N as some plants don't tolerate it very well in excess.

If both N and P, regardless of the sources, drops to near zero, and plants haven't stored enough in its tissues, then plants will stop growing. The first visual sign is reduced photosynthesis which you can see from the reduced pearling. Adding more CO2 in such instances will not increase photosynthesis.

As for measuring CO2 concentrations, the degas method is superior to the ph/kh method since any acids or OH- does not affect degassing. If there are acids in the water, the pH will be lower which makes it seem like there's more CO2 than actual. For myself, since I add very little CO2, I no longer bother to measure. It just isn't necessary.

See less See more

Save

sfshrimp

· #6 · Oct 1, 2016

Is this your tank?

Solcielo lawrencia said:
CO2 does not need to be "good" for plants to pearl madly. The above photo shows Rotalas pearling at less than 15mg/L of CO2 under high light and very low nutrient levels. Plants can pearl just as much with <10mg/L of CO2.

As for dosing, a little goes a very long way. Depending on other parameters, 0.1mg/L of PO4 and 1mg/L of nitrate should be sufficient. The nitrate will probably be used up faster, depending on how much CO2 is available and plant health, so may need to be supplied more often if fish waste doesn't provide enough nitrogen from ammonium. Urea, ammonium, and nitrate are all sources of N and plants do have specific preferences for which ones they prefer and at certain ratios. Dosing nitrate alone is not the best way to provide N as some plants don't tolerate it very well in excess.

If both N and P, regardless of the sources, drops to near zero, and plants haven't stored enough in its tissues, then plants will stop growing. The first visual sign is reduced photosynthesis which you can see from the reduced pearling. Adding more CO2 in such instances will not increase photosynthesis.

As for measuring CO2 concentrations, the degas method is superior to the ph/kh method since any acids or OH- does not affect degassing. If there are acids in the water, the pH will be lower which makes it seem like there's more CO2 than actual. For myself, since I add very little CO2, I no longer bother to measure. It just isn't necessary.

Save

Solcielo lawrencia

· #7 · Oct 1, 2016

Yes.

Save

sfshrimp

· #8 · Oct 1, 2016

Solcielo lawrencia said:
Yes.

Looks good. Very similar to mine. I run high light, EI dose and very little c02. Is that what you are doing? Almost no algae.

Save

Solcielo lawrencia

· #9 · Oct 1, 2016

I no longer dose EI. I haven't in almost a year. There's ample evidence that adding so many salts and traces are detrimental to both plants and livestock. I also killed off all my shrimp and snails and half my fish from dosing the full 0.5ppm of Fe from CSM 3x week. I couldn't add any invertebrates for several months because the water was so toxic; they would die within hours. It was so toxic that if I watered houseplants with it, they would wilt and die. Now, the plants have never been healthier in the two years the tank has been running. Fish and shrimp are much more active and healthy. I'm using way less CO2 (from 40+mg/L a year ago) and fertilizers. I've more than tripled the time between CO2 refills, and I barely touch the dry fertz. And the fish and plants are much healthier.

Save

Wasserpest

· #10 · Oct 3, 2016

SteveMcdermit said:
Thankyou all,
i do run injected CO2 and i will invest in buying a pH pen for future use, one last question is i want to start using Estimative Index for my method of dosing, should i start with a half dose and build up to a full dose overtime, or should i completely forget about doing that at this stage?
I guess ill start experimenting and play it by ear with the CO2 also within reason ofcourse. aha
Thanks for all the advice!

One of the requirements for successful application of EI is that you religiously do 50% water changes every week. I would start with half doses, because if your plants are somewhat algae ridden, they will not take full advantage of the nutrient load.

Personally, I don't shun some basic measuring, at least in the beginning. It is not needed for excess dosing like EI, but if you want to supply just the right amount, you will need to test to figure out how much of the supplied ferts your specific tank uses.

Save

1 - 10 of 10 Posts

This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.

Top Contributors this Month