Need help with plant ferts

[IceH2O]

I use 1.75 wpg of light, have mostly stem plants and sand substrate, no injection.Seachem root tabs for root feeders.

I have some brown algae on the glass and some of the plant leaves. I have a nice tuff of green algae on an ornament near the intake tube, I kind of like the way it looks.

I have been using something called PlantGro by Hagen, but I think its just a trace fert and not carbon.


I can't find flourish or flourish excel in town, will order some tonight. Should I buy both or is one better than another?


For future references what dry ferts should I get to mix my own water column ferts? A link that shows levels needed for a 75 gallon tank would be a plus also.

 

[Captain Hook]

For calculating levels, the best one I know is if the APC Fertilator I like it because it will add up all the variables at once.

There's a downloadable program by Chuck Gadd that will also calculate levels. I've found there is a slight difference between the two when using teaspoons. Chuck Gadd's calculator program

There is a PlantGro fertilizer that is for traces and iron, and there is one that has N-P-K in it. Flourish Comprehensive is also a trace fertilizer. Flourish Excel is a liquid carbon source. If you're getting Excel for a 75 gallon tank, I'd suggest buying a big bottle.

The dry ferts generally used are KNO3, K2SO4, KH2PO4, CaCl2, and MgSO4. You may not require all of these. KNO3 and KH2PO4 are pretty much considered the basics.

If you can, try to find out what is actually in your tap water. If it's high in nitrates, you might not need to add any KNO3. Same goes for phosphates, KH2PO4 might not be needed. Calcium and Magnesium levels could be high enough from the tap as well. This of course assumes that you are doing large and frequent enough changes to reach these levels.

 

[IceH2O]

Thanks...



My tap water has 2.5 ppm of natural nitrates.

Mg and Ca are measured using GH right? If so they are very low, around 2 or 3.

Phosphates I'd need to test for, but going by Chuck Gadds site :

"If you aren't adding CO2 to your water, and the CO2 level based on the pH and KH indicates more than 5ppm, then it is very likely that some other buffer (such as phosphate) is present in your water. "

According to his chart I have 14 ppm (ph 6.8 and KH 3), so phosphates are most likely there, just don't know to what degree.


edit: Okay I went to greg watsons shop and bought
KNO3
K2SO4
CaCl2
MgSO4.7H2O

The Ca will raise my KH right? If I add 3 tsps I'll be adding 16.85 + my normal 3 for a total of 19.85 ppm..How much will that make my PH rise?

If i'm not injecting do these values still count for me or do I need to be at the lower end instead of the middle?

 

[Captain Hook]

Hmm...where to start. Try to get a water quality report, preferably 2005, from your water supply people. They made me a spreadsheet with the nutrients I requested. In early 2005 they also mailed me the 2004 reports. GH is mostly made up of Ca and Mg, but that does not give you their individual values. It could be mostly one or the other.

It would be very good to know what kind of phosphates you have in your water as well. Mine is very low, about 0.1 ppm, but it could be alot higher in your case.

Is it too late to add some KH2PO4 to your order? It would be good to have it, just in case. If it is don't worry you can find other sources, as long as you're not embarassed buying an enema

As far as I know, adding Ca or Mg will not change your KH.

GH is not measured in ppm.

 

[IceH2O]

Water report is out of the question as I'm on an individual well system.

That fert caculator is pretty awesome. I was wondering if when you do a water change say 50%, do you only add back enough fert to match the 50% of water you're replacing and is it best to mix all the ferts together in one gallon of water and pour it into the tank or mix them individually?

 

[Captain Hook]

Hmm, maybe try getting a phosphate (PO4) test kit then. That would be something that's good to know.

I add enough fertilizer to get the levels I want in the whole tank, not just the new water. Tom Barr says the maximum uptake by plants with high light and high CO2 is about 0.4 ppm of PO4 and 4 ppm of nitrates (NO3) a day.

Based on this I usually dose around 6-8 ppm N03, 1.5 ppm P04, and 9 ppm K every 3 days. I have been experiementing with changing this a bit. These are just my numbers, not meant to be your guideline.

When I dose, I use a small container with about 100-150 mL of hot water. I add all or most of the dry chemicals I want to dose, put the lid on the container and shake. Then add about 200 mL cool water and pour into the tank.

An easier way to do it is to mix a solution. Just some rough numbers for a guideline, 15 g KNO3, 15 g K2SO4, 4 g KH2PO4 in 500 mL of water. You can do this so 1 mL of your solution will give you 1 ppm of NO3. Or less potent so 5 mL will add 1 ppm to the tank.

 

[IceH2O]

Appreciate the help.

I'm guessing since I'm medium low light and no injection my plants won't use as much fert. I could probably get away with once a week dosing.

Since i don't inject yet, are the ferts going to help algae grow or will the plants still outcompete the algae?

 

[IceH2O]

Medium Low light ( 1.75 wpg ) + dry ferts - co2 injection = ???????


Since there is no injection, and a lower level of lighting do I need to stay on the low end of the scale? ex- nitrate 10 -20 should I stay closer to 10 or does it matter?

 

[Captain Hook]

What kind of lighting do you have? About 130 watts right? Is that 2 - 65 watt bulbs? How long has the tank been running?

Without CO2 injection you will have slower growth rates and as a result, lower nutrient demands. If your fish load is fairly low, you will probably need to add some nitrate so it does not reach 0. This is assuming your water isn't too high in NO3 to begin with. If you run out of nitrates, you will have algae problems. Same thing with PO4.

The fertilizer moderator on APC, Edward, has developed a system of dosing daily. He strongly believes that growth is better with fresh nutrients added daily. I usually dose every 3-4 days. In your tank you could probably go with one large dosing after water changes (assuming weekly changes) or split that dosage into two or three times during the week.

I don't have CO2 going in my 25 gallon that has about 1.5 wpg of fluorescents. I went a long time without adding any liquid fertilizer. Only Jobes sticks for lush ferns and palms in the substrate. The tank was mostly crypts and java fern with a low fish load. Now it has some vals and Hygrophila polysperma so I add small amounts of liquid fertilizer, usually around 5-1-10, once or twice a week.

This method of supplying lots of nutrients through gravel sticks seems to be becoming outdated. The new and preferred method is to stick with liquid fertilizing only. It's easier to control what's in the tank like this.

 

[IceH2O]

Yeah its 130 watts CF 65 watts a piece. This tank has only been up since 1st week of Feburary 2006.

It has:
2 soon to be 3 clown loaches
4 dwarf gourmais
2 senegal birchirs
MT snails

So I should stay at the lower level and just check my levels around mid week and see if it needs to be hit again.

I noticed some green spot algae in my 55. Isn't that caused by a phosphate deficency? Maybe I need some Fleet after all.Also my 75 has green hair algae on a rock shelf ornament, but I like the look of it so I'm not worried about it as long as it stays there.

Also do these dry ferts help give out carbon or do I still need to buy Excel?