GDA was keep on coming back and i have to clean the glass everyday, at Tom's Recommendation i added 14 bushy nose Pleco, they did help control the algae little bit but glass would be covered with GDA everyday. most of the bushy nose died one by one due to CO2 while other fishes were fine, i think BN are very sensitive to CO2, now i only have 4-5 left. during all these experiment i was Dosing EI and i have also noticed that adding more KNO3 made the GDA worse.
now let me explain why GDA Occur, i know what am about to say would cause debate and there will be a disagreement but you have to try it yourself before questioning. i also discovered low PH water is Prone to GDA when using EI dosing, why? because when using KNO3, Bacteria have to convert NO3 back to NH4 for the plants, plants are normally covered with Bacteria who convert this, but in low PH water Bacteria aren't very active. this might explain why some people have problem when dosing EI and using very low PH. now on the other side EI worked very well in high PH water, keep in mind high PH water is beneficial for Bacteria and they are most active under these conditions.
if you mix methods you get GDA, it explains why i was getting GDA while dosing my own recipe, because i already had tons of fert in the water to begin with, i suppose to do many water changes before i started dosing my recipe. let me explain it better, if you are dosing EI and then switch to Seachem while you already have tons of nutrients in the water, you are likely to get GDA.
i do not get GDA after making the following changes:
Phosphate does not cause GDA, i now add 1ppm of PO4 3x week while using my own recipe which adds 1ppm NO3 and 0.7ppm of NH4 per day. i think having low NO3 might be the main reason GDA stooped and it had nothing to do with PO4. now plants are growing much better and GDA is slowly becoming dark black and falling off the plants, rocks etc. keep in mind my PH is very low and KH is 0. am now using more light than before and GDA hasn't returned yet, this will clear your doubt about who think GDA is caused by high light.
i think too much KNO3 was the real cause of GDA under lower PH tanks. i can Confirm PO4 was not the cause because i still dose the same amount 1ppm 3x week.
i know we have many EI defenders out there and this Thread is most likely to see argument, debate, disagreement and let me be clear, i did not say EI doesn't work or cause Algae, i have said i found that having too much NO3 in low PH is Prone to GDA and EI is the only method which adds tons of NO3 in the water and i have already explained why this occur.
Try it before you disagree, it might take 2-3 weeks but you will get your answer after making those changes.
lets start with this first:
The amide nitrogen is NH2.
All the problems associated with the introduction of an easily digestible for plants, but stimulating algal growth of the ammonium form of nitrogen NH4 + can easily be avoided by making an even better source of nitrogen for plants - amide nitrogen which is half of the nitrogen source in Seachem Flourish Nitrogen ™ . The amide nitrogen - are compounds in which the nitrogen bound in the form NH2. This will give aquatic plants easily digestible source of nitrogen like NH4 +, but is not available to power the algae:
"... This means that the ammonium nitrogen is not present as free ammonia or ammonium as well as part of a more complex molecule, which can be expanded to plant ammonia and recycling. Algae In theory it would also absorb, but our research and beta testing have shown that this does not occur (ie, very low and is not algae, many have documented that algae are down). " (Gregory Morin, Ph.D. Seachem Laboratories, Inc., Research Director - fins.actwin.com )
now lets take a look at algae:
keep in mind NH4 and Urea doesn't stay in NH4 form for very long in the water, eventually it is converted to NO3 if plant doesn't use it, this is the only good reason to have good colony of bacteria, if you have low KH/Ph i suggest adding it in small amount.
ok now lets start by looking at the graphs, if you look at it carefully you will see how Urea and NH4 can increase the Algae growth at much faster rate compare to NO3, but keep in mind, it shows algae growth increase as the days pass by, you wont see any urea or NH4 in your tank for more than couple of hours after adding it, any excess urea/NH4 will be converted to Nitrate within the same day or maybe next day, only NO3 levels can go up. now look at the graphs and you be the judge.
NH4 act as quick boost to plants and Algae and should be used in very small amount. start with 0.1ppm of NH4, Urea on the other hand works little different than the NH4, it break down into the plants in such a way that algae cannot get much chance to use it, something to do with algae lacking enzymes. Urea is better and can be used in higher dose than NH4, you can start with 0.5ppm of Urea if you want to test it.
When using Urea, you must be careful not to overdose too much when using high lights, you will start to see some Blue green and slime algae on the leafs, this is a clear sign of too much light and excess Urea, if this happen dose less.
i apologize about one thing which no one knew or was confused about, i was also confuse about this, i came to find out bacteria has nothing to do with plant taking up Nitrate. someone told me that it does and i used that info till now, but this is not the truth. none of the members here pointed it out, but at the APC they pointed it out. But there could be some truth to it if someone here could explain it better.