Jim

I just purchased the following fertilizers (85G planted discus tank) from Greg Watson, but am confused about exactly how to go about mixing these and frequency of the dosing.

Plantex CSM+B Plus Iron
Mono Potassium Phosphate (KH2PO4)
Potassium Sulfate (K2SO4)
Potassium Nitrate (KNO3)

I think these are the right macro/micro nutrients, but the more I read online to figure out the dosing question, the more confused I become. I typically do 40-50% percent water changes once a week and think the estimative index method would be the right way to go.

Based on the following about my tank, can someone please help me figure this out in very simple terms? I have used Flourish products in the past and am new to this method -- I'm finding the calculators, etc. that are online to be a bit confusing.

Here's a rundown of the tank:

85 gallon
3.5 wpg light for 10 hours/day
Approx. 20 plants in the tank (a combination of swords, anubias, anacharis, hairgrass)
Fish load is moderate to heavy
Pressurized CO2 - 25 ppm
pH - 6.9
KH - 125 ppm (7 degrees)
GH - 143 ppm (8 degrees)
Nitrate - The test is not totally clear, but its somewhere between 0 and 5 (closer to 0)
PO4 - 5.0
Nitrite & Ammonia - 0
Temp - 84

I'm in the process of switching from very hard tap water to RO water (for my discus). I just introduced the RO water into the tank this wekeend (50 percent RO mixed with existing tap water in the tank). I wanted to avoid stressing out my fish, so I went for a 50/50 mixture. So far, so good.

Among other things, I'm trying to get my PO4 level down because I am dealing with an ongoing green algae battle (you'll notice its high at 5.0). This is another area of concern -- I know that I'll be adding PO4 as part of my dosing -- should I leave this out of the ferts mixture until my existing PO4 levels decrease?

I also added RO Right to the new water, but in hindsight I probably should have added less than it called for (given the high KH and GH already in my tank).

Any recommendations are greatly appreciated!

Jim

MatPat

First thing is to try and figure out the actual volume of your tank. I have used the total volume multiplied by 0.85 to get the volume of my tanks. For your tank this would be 85 x 0.85 = 72.5. I think this is pretty close but if you are using a sump, be sure to add in the volume of the sump or other large filters.

If you are using Chuck's Planted Aquarium Caculator select your nutrient compound from the pull down list. After that, select a measurement, either grams, teaspoons, or tablespoons. I use teaspoons for ease of use. Go to the tank size and enter the volume you calculated above 72.5 gal (I rounded up to 75gal for filter/s). Where you can choose Mix solution or Add dry compound directly to tank, select add dry. I use the dry method so I don't have to fuss with mixing a solution. This will save you the frustration of trying to mix up solutions while trying to learn how to dose.

For your tank, if I select NITRATE in Potassium Nitrate (KNO3), add 0.5 tsp for the amount of compound, the values at the bottom will show the amount of NO3 in 1/2 tsp = 6.04ppm KNO3. I usually add my dry ferts to a small bottle of water, shake and then add them to the tank. Some do add their dry ferts directly to the tank.

You can go through each of the ferts this way and see what they will add in certain amounts.

1/2 tsp KNO3 ~ 6ppm Nitrate
1/8 tsp KH2PO4 ~ 1.5 ppm Phosphate

You may or may not want to add Potassium Sulfate to your tank. Please note that there is Potassium (K) in Potassium NItrate (KNO3). You can use the Nutrient Compound pulldown to select POTASSIUM in Potassium Nitrate also!

I mix up my CSM+B at a rate of 2 tablespoons to 500ml. I dose 30ml every other day in my 75g. I have a lot of stem plants so the tank is a fairly fast grower and as a result will use more nutrients.

I think Greg's site says to use 1 tablespoon of CSM+B in 500ml. For this you would use (I think) 6.25 ml of CSM+B for every 5ml (teaspoon) of Flourish. Please double check his site for the mixing instructions.

I would leave out the PO4 dosing until you get the PO4 lowered either with water changes or plant plant uptake.

You probably didn't need to add the RO right to the tank when mixing it with your tap water, but that would depend on your tap readings and how low or high you want your GH and KH to be. Hindsight is always 20/20 ain't it

1/2 tsp of KNO3 and 1/8 tsp of KH2PO4 would probably be a good start for your tank (after you get the PO4 lowered). Add the ferts after the water change and at midweek. You could then add your CSM+B the next day. I usually like to test my NO3 and PO4 (when I change my dosing routine) before the water change so I know what the tank has used throughout the week.

I would probably add some more plants to get the tank started. You can always trade/sell them if you decide you don't want them later. However, the more you start out the more nutrients the tank will use and the less chance algae will take hold.

I hope this didn't confuse you more If I did confuse you feel free to PM me or keep posting and people will help you out.

discus

Hi Jim

Yes this was confusing for me at first as well. Here are a few recommendations.
I dont want to sound like a pusher here but you should pay a visit to the following thread within APC
http://www.aquaticplantcentral.com/f...v2005-new.html
Once you pay a visit you should read the articles in the order presented. Within the articles you will be provided with recipes for mixing solutions and explanations of how the PPS sytem may be used.

You should also download the XLS file as this will help you keep track of your dosing regimen and both Edward and I are usually here to help out with questions if related to PPS (Perpetual Preservation System)

In addition you may also choose to post your XLS data in the following thread
http://www.aquaticplantcentral.com/f...eets-here.html
this is where you get personalized service at APC and a look to see what your dosing and anyadjustments required if any.

And to add to all this there is yet another discussion thread
http://www.aquaticplantcentral.com/f...on-thread.html
Here you will find a wide cvariety of comments that will aid in your decision and knowledge.

Boy I do sound like a pusher, a thread pusher.

In any case my moto is read read read ask ask ask and then ask some more questions.
Good luck and keep us posted

Jim

Thanks again for the recommendations. One quick question -- does the PMDD Pre-mix solution (Greg Watson) need to be refrigerated and does it matter if the bottle is clear or dark?

Thanks,

Jim

plantbrain

Jim,

Due to the fish loading, you will have less need for KNO3, perhaps 1/4 teaspoon 3-4x a week. If you have 7-9 adults and feed them well, expect about 50% of the N to come from the fish loading.
I've had many Discus planted tanks and there are many folks in the bay area that keep these, the ratio of about 1/2 the N is about right needed for these well feed tanks.

1/2 teaspoon is fine till you get the fish feeding going.
1/8 on the KH2PO4 on the same day as the KNO3.

Blend the tap with the RO to get about 2-3KH. Makes sure the GH is about 4-5.

Traces: 15mls 3x a week will be plenty.

If you want to test for PO4/NO3 you can, but most algae and other issues are related to CO2 and low nutrients, I've yet to see a plant issue due to excess.

Fish might not like the high NO3, but if you do frequent water changes, there's no chace of that. Keeping the CO2 in good shape will address the rest.

So all you'll do is dose and make sure the CO2 is good and feed the fish, do the water change.

The algae you have, you'll need to get in there and prune and remove as much as you can. Keeping things stable will acheive that. You do not need to add more PO4 till the levels drops to 1.0ppm or so, provided the test kit is accurate.

Regards,
Tom Barr