I recently set up my tank.

180 gallon, 75g sump filter with a Fluval 404 for mechanical/carbon filtration. The only fish load at the moment is four SAE, and 10 ottos which I haven't fed due to the assumption they would feed on algae. Temp is around 78 F. (edit) - forgot to mention lighting which is four 95W CF bulbs and two 90W T5 bulbs all 6700K (makes around 3.1 watts/gal.).

The CO2 is probably around 20-25ppm based on the color of the drop checker. I'm using the EI method for fertilization. I put in 0.75 tsp of KH2P04 on Friday, and Monday. I also dosed 1.5 tsp of KNO3 the same days. I used the recommended quantity of Seachem Flourish on the same days. Today (Wednesday) I noticed Spirogyra (silk algae) growing on the plants and driftwood. A sizable amount but nothing that overly concerns me.

The plants are growing like weeds and have great color. According to the following article (Aquarium Algae ID (updated)) this algae is caused by an excess of nutrients. I was surprised because the amount of ferts I dosed was half what I calculated for my water volume. I thought it best to start out low and build up as the plants matured. The plan load is as follows: ~50 assorted stems, ~15 val, 5 HC patches around 2" in diameter, 2 swords, and 4 aponogetens.

I thought the best thing to do to keep things from getting out of hand was to not dose ferts today (Wednesday) and then go a little lighter on my doses when I did a water change this Saturday. Seem like a reasonable plan?

Any advice appreciated.

Hi,

How long ago was the tank setup? It could be still cycling...........

> 3 wpg is a lot of light. You may want to reduce that to 2 wpg or so if possible.

High light = high demand for nutrients (including c02). So, keep in mind. Lower light = less demand.

How are you injecting/distributing your c02?

I have a 180 and keeping the flow/current so that nutes are available all over is quite a job.......

Are you just using the canister for flow? The 404 seems undersized for your tank........

What is in your sump? Bio-balls, anything? What size pump drives the sump?

Are you using 4d KH water in the drop checker?

You should dose regularly. K and P on Mon, Wed, Fri and trace on Tues, Thur, Sat, and the min 50% WC with condition and/or GH booster on Sunday.

Daily dosing would be better if possible. If so, wait 4-6 hours after dosing the K and P to dose the traces..........

Can you post a pic?

About six months ago - yeah - LFS couldn't get the plants in - gave up and ordered from aquariumplants.com. Anyway - I kept the lights off for that time and did three 50% water changes the week before I stocked with plants. I figured with a low fish load and a large volume that the surfaces and gravel bed would have plenty of bacteria. Think I might be wrong on that?


I'll turn off one of the CF banks which will leave me with about 2 wpg. My lighting is left over from my saltwater setup which had 4 T5 and 4 CF for about 5 wpg.


A mazzei injector. Aquatic Eco-Systems: Mazzei® Venturi Injectors. The bubbles are too much to count - likely a cost of the sump.



I have two return pumps running through the sump. One Mag 9.5, and a Iwaki 30 RXT. This gives around 1300 gph turnover with the head loss taken into account. The sump just has gravel (Eco Complete same as display) and a couple of driftwood/stones. I plan to use that side to grow some more plants to sell back to the LFS. Nothing is in the business end of the sump except a 1000 W heater. The 404 is in addition to the rest of the tank - I added it for the sake of running carbon and mechanical filtration which works best under a forced flow as opposed to gravity fed via a sump. The flow looks good in the tank - I make that judgement based on the CO2 bubbles that float around - they are getting good distribution throughout the tank and it doesn't appear to have any dead spots. Also not too much as the plants are gently moving in the flow. I use spray bars at the back/bottom of the tank to distribute the flow.


Yes, bought online from here: KH Standard


I've only dosed twice since I added the plants last week. I was dosing K, P, and liquid ferts all on the same day. Does alternating make a difference?

I'll post pictures tomorrow when the lights come on.

Thanks for your help!
Aaron

I don't think your dosing is correct. Adding 1.5 tsp of KNO3 to 160 gallons of water only gives you about 9ppm of nitrate and less than 5ppm of potassium. I think you want to maintain at least 15-20ppm of both nitrate and potassium, depending on the uptake. Especially with co2 and high light, this sounds very lean to me.

Adding .75 tsp of KH2PO4 is giving you a whopping 4ppm of phosphate. Suggested levels are only 1 - 2ppm.

Here are some numbers if you want to see how you might adjust things...

KNO3: 2.6 tsp will give you 15ppm in 160 gallons of water, and 9.4ppm of potassium
KH2PO4: 1/3 tsp will give you 2ppm in 160 gallons of water

Adjust frequency of dosing depending on uptake/co2/lighting - you might need to add this 3x/week. If it were a low light tank or non-co2, I would add 1x/week at the water change only.


Edit: Wait, didn't see that about the sump! This changes things a lot.

So if we now assume 230 gallons of water:

KNO3: 3.8 tsp
KH2PO4: 1/2 tsp

This will give you the same results as above. What you were adding before, was giving you 6ppm of nitrate, 3.79 ppm of potassium and 3ppm of phosphate.

Hey,


So, the tank was setup with some fish, but NO lights and no plants for MONTHS? Just curious.

I am sure the tank is mature after 6 months, but remember that bacteria grow with the abundance of food for them. Low fish loads, low feeding etc, there is no need for a huge number of bacteria, regardless of the amount of SPACE available for them to occupy.

The lower light can be temporary until things are going well. It is easier to add than take away light.

I would set duration to about 8-9 hours at first.

I ordered from them too, I think they have good stuff. AP.com that is.....

What size Mazzei, and what are you driving it with? The mag 9.5?


Plants need food just like fish.

You should dose as Carissa suggested. You will be able to adjust this amount as your tank grows in.

C02 is most likely going to be your biggest issue long term......

Remember that as the PLANTS GROW, they will need more ferts, INCLUDING C02, so don't forget that in the coming weeks and months. You will need to increase c02 maybe more than the other ferts..........

You can't set it and forget it, unless your tank NEVER changes in bio-mass lol

You can dose macros and micros on the same day, just know that some traces with Iron may bind with P04. This will make both elements unavailable to the plants. Waiting 4-6 hours between will resolve this.

Hope this helps.

Thanks for the advice guys. Carissa - right or wrong I was starting a bit low on the ferts with the idea that the low plant load wouldn't need it. I see the error of my thinking now due to the ppm argument. I've tried to absorb a lot of information before starting and appear to have gotten a bit confused here. I'll have to check my math on the KH2P04 - not sure how I got off there.

Gerry, the tank had no fish for those six months - it was just a bucket of water with a nasty film on the top.

The Mazzei is the $50 version. I have it plumbed with my Iwaki return on an alternate loop - I change the flow depending on the fineness of the bubbles - if I run the full output of the pump it creates large bubbles for some reason. I plan to buy another one next month to install on the other return to allow diffusing more CO2. I assume I'll notice the drop checker turn more blue if I need to increase CO2 injection - true?

Thanks for reminding me about the PO4 and iron binding issue.

Again - thanks for the advice. I'll implement and see how it goes.

I was hoping someone could help me understand how Carissa arrived at her numbers? I used Chuck Gadd's online calculator (4 tsp KNO3 dissolved in 1 ml H20 would add 240 gal of water 20 ppm of NO3). Carissa recommended using 3.8 tsp in 230 gal for 15 ppm. What is the formula one uses to determine ppm in a gallon of water for each of these chemicals?

I created a calculator a while back in Excel so I wouldn't have to calculate anymore. You can download it on my site if you want. I used the same site you went to, to get my numbers.

If you want to do your own calculation, here's what I have in my Excel spreadsheet:

Nitrates (KNO3): PPM you want / (905/gallons) = # of tsp you need to add
Phosphate (KH2PO4): PPM / (884/gallons) = # of tsp
Potassium (K2SO4): PPM / (711/gallons) = # of tsp
Iron in Plantex CSM+B: PPM / (87.592/gallons) = # of tsp

To figure out how much potassium you are getting if you add x number of tsp of KNO3: #tsp / (572/gallons) = ppms

I hope these calculations are good, if anyone sees any errors please let me know.

Thanks Clarissa. Just to confirm as well. If I'm doing 50% water changes weekly then I should dose half what I want my target ppm to be? So if I want my NO3 to be 30 ppm I should dose 15ppm. I understand that doesn't mean I will actually get to 30 ppm as the plants are taking NO3 out of the water; however, I will never exceed 30 ppm. That is what I gathered from Tom's EI article.

I still have the string algae but it hasn't overtaken the tank. I've been getting in there each day and pulling it out for now - not a big chore but I definitely want to solve the problem long-term as this won't last for a daily chore.

Thanks,
Aaron

Ok, you're on the right track but that's not quite how it works. The purpose of EI is to ensure that nothing is ever zero. Exact ppm's don't matter that much (one reason why test kits aren't needed), inasmuch as it's never allowed to get to zero and start limiting your plants.

So to accomplish that, measurements have been made of how much of each nutrient a high light, co2 injected well planted tank would use up in a given week. EI suggestions for dosing are based on this assumption, so dosing can be adjusted downward a bit if a tank is lower light, non-co2, or not well planted (see this link for suggested dosing: EI light: for those less techy folks ) What you are essentially doing is taking those suggested ppm's and dividing by 3 assuming you are dosing 3x/week. The suggested ppm's are the total weekly rates of uptake, not necessarily what you need to have in your tank at any given time during that week.

For example, if you know you will probably burn $50 gas in your car each week, you don't need to have $50 worth of gas in your car at all times, as long as you are adding enough weekly to keep up with what you burn. The whole idea of EI is that you never run out of gas, and at the same time you never overfill your tank either.

So the idea is that you are adding enough that you will very likely never get to zero on anything, but on the other hand the 50% water changes weekly ensure that you will also never get to double the total ppm's that you dose on a weekly basis. Maintaining these levels of fertilizers has been shown to have no adverse effects on fish health or cause algae, even though you theoretically can have what may be considered higher than necessary levels of fertilizers in your tank at any given time.