Rough algae on plants, high nirtates

slimyslippers

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Hoping you guys can help with an issue I am having with my plants. They seem to be stunted and/or not growing. They also have some sort of algae growing on their leaves that I believe may be inhibiting their ability to photosynthesize. Maybe I am wrong. I am also dealing with very high Nirtates. I did a 50% water change this morning. It's a 220g with 40g sump. They get roughly 12 hours of light per day. All other water parameters seem fine (0 ammonia, 0 nitrite, 7.4ph, 40KH.) I do have pretty hard water, though. This is also the fert I have been using. I have read it's garbage, though..
 

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Flourish is a micro nutrient fert. As long as nitrate and phosphate levels are high enough, it may be all you need. Heavily stocked tanks will produce plenty of nitrate and phosphorus.

Excel is used to kill algae by many, but is of little value as a CO2 source.

As said, regular water changes to keep the nitrates down will go a long way to improving the health of your tank. Applying Excel directly to the algae (with filters and pumps off for a minute or two) will usually kill algae in time. Apply daily until dead. This will help control algae, but does not solve the problem. Applying it directly to delicate plants, like mosses could do damage.

My low tech planted tanks with low stocking test at -0- nitrates. I use fert to raise it to 5ppm. For me, that helps keep the algae at bay and the plants are fine. I also find that if do 50% weekly water changes, the algae stays away (mostly). Water changes remove more than nitrates. You need a routine that works for your particular tank. Any changes you make will take time to see results.

Incorporating emersed plants can help with the nitrates too. Because they have unlimited access to CO2 from the air, they use more nutrients.

Good circulation in all parts of the tank (no dead zones) can be helpful as well. The planted tank folk like to see their plants moving in the current as an indication of good circulation.

12 hours of light could be too much, but it also depends on the intensity. Decreasing the intensity and or duration can help discourage algae as well, as long as the plants remain ok.
 

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You just need to get the nitrates down and then ur plants will start growing again they are probably stunted from that so just try to get your water quality better

Flourish is a micro nutrient fert. As long as nitrate and phosphate levels are high enough, it may be all you need. Heavily stocked tanks will produce plenty of nitrate and phosphorus.

Excel is used to kill algae by many, but is of little value as a CO2 source.

As said, regular water changes to keep the nitrates down will go a long way to improving the health of your tank. Applying Excel directly to the algae (with filters and pumps off for a minute or two) will usually kill algae in time. Apply daily until dead. This will help control algae, but does not solve the problem. Applying it directly to delicate plants, like mosses could do damage.

My low tech planted tanks with low stocking test at -0- nitrates. I use fert to raise it to 5ppm. For me, that helps keep the algae at bay and the plants are fine. I also find that if do 50% weekly water changes, the algae stays away (mostly). Water changes remove more than nitrates. You need a routine that works for your particular tank. Any changes you make will take time to see results.

Incorporating emersed plants can help with the nitrates too. Because they have unlimited access to CO2 from the air, they use more nutrients.

Good circulation in all parts of the tank (no dead zones) can be helpful as well. The planted tank folk like to see their plants moving in the current as an indication of good circulation.

12 hours of light could be too much, but it also depends on the intensity. Decreasing the intensity and or duration can help discourage algae as well, as long as the plants remain ok.
That’s a better explanation
 
  • Thread Starter
  • #4
Flourish is a micro nutrient fert. As long as nitrate and phosphate levels are high enough, it may be all you need. Heavily stocked tanks will produce plenty of nitrate and phosphorus.

Excel is used to kill algae by many, but is of little value as a CO2 source.

As said, regular water changes to keep the nitrates down will go a long way to improving the health of your tank. Applying Excel directly to the algae (with filters and pumps off for a minute or two) will usually kill algae in time. Apply daily until dead. This will help control algae, but does not solve the problem. Applying it directly to delicate plants, like mosses could do damage.

My low tech planted tanks with low stocking test at -0- nitrates. I use fert to raise it to 5ppm. For me, that helps keep the algae at bay and the plants are fine. I also find that if do 50% weekly water changes, the algae stays away (mostly). Water changes remove more than nitrates. You need a routine that works for your particular tank. Any changes you make will take time to see results.

Incorporating emersed plants can help with the nitrates too. Because they have unlimited access to CO2 from the air, they use more nutrients.

Good circulation in all parts of the tank (no dead zones) can be helpful as well. The planted tank folk like to see their plants moving in the current as an indication of good circulation.

12 hours of light could be too much, but it also depends on the intensity. Decreasing the intensity and or duration can help discourage algae as well, as long as the plants remain ok.
When you're doing water changes, are you also gravel vaccing or are you simply siphoning the water only?

So after yesterdays 50% pure water change, and 25% today with a gravel vac, I am no better off nitrate wise.

Unless it takes time, but I would have thought manually removing 75% of the total water would show some improvement.. I am following the instructions to a T, when it comes to dosing, shaking, letting it sit. I am using the API master test kit. 5 ml water, 10 drops bottle 1, invert a few times, shake bottle 2 for 30 seconds, 10 drops vertically, shake for 1 minute, let sit for 5 minutes before reading.

Funny enough, the test strips I also have, show 0 nitrate. Pretty wild swing..
 

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Probably gravel vacuuming to but that’s extra siphoning will do the job

Are your fish acting strange or are they healthy because if they are healthy I wouldn’t worry about it and your plants might just be dormant or building up enough strength to grow

Also what kind of fish do you have tank size and size of fish
 
With those species of plants and that fish stocking, you don't need any fertilizer to begin with. Potassium is the one that might sometimes be scarce, hence some potassium sulphate salts can be handy to have.

Looking at the leaves, I see physiological stress, I see algae infestation, and perhaps signs of anthocyanin. I assume you run lights as they came out of the box / with this tank.

Ferns and crypts (little species dependent) develop evenly, dark green tissue without algae, in the shades. If you want to keep the lights strong, improved water flow, frequent removal of dissolved organics, and perhaps some cooler temps can help.

But I'm not sure if your fish will appreciate those circumstances. I do know they won't mind the shades either.

Excess nitrates? Your plants don't care. Neither do algae. Both plants and algae do fine in 5 ppm nitrates/nitrogen or 50 ppm water. Tap water should have less than 5 ppm, but place a vase with tap water under bright light, and you'll see green water develop. (in planted tanks it is usually not the free-floating form of algae that appears, but rather hairs and filamentous)

cheers
 
So after yesterdays 50% pure water change, and 25% today with a gravel vac, I am no better off nitrate wise.

Unless it takes time, but I would have thought manually removing 75% of the total water would show some improvement.. I am following the instructions to a T, when it comes to dosing, shaking, letting it sit. I am using the API master test kit. 5 ml water, 10 drops bottle 1, invert a few times, shake bottle 2 for 30 seconds, 10 drops vertically, shake for 1 minute, let sit for 5 minutes before reading.

Funny enough, the test strips I also have, show 0 nitrate. Pretty wild swing..

Your nitrates are above range your test kit can effectively read. Dilute tank water with RO drinking water from market (nitrate free) to get a 25% solution, (1 part tank water, 3 parts store bought water) Then run test again, multiply that x4 to get actual ppm in tank.

Do you have a phosphate test kit? If not you should. May need to do same procedure to get a proper reading on it as well .

If phosphate and nitrate are as high as I expect your DOC load is also way out of range as well. Unfortunately common aquarium keepers can’t actually run true DOC tests, takes a real laboratory to do it.
 
  • Thread Starter
  • #8
Your nitrates are above range your test kit can effectively read. Dilute tank water with RO drinking water from market (nitrate free) to get a 25% solution, (1 part tank water, 3 parts store bought water) Then run test again, multiply that x4 to get actual ppm in tank.

Do you have a phosphate test kit? If not you should. May need to do same procedure to get a proper reading on it as well .

If phosphate and nitrate are as high as I expect your DOC load is also way out of range as well. Unfortunately common aquarium keepers can’t actually run true DOC tests, takes a real laboratory to do it.
I don't have a phosphate test kit but I will look into getting one!

Are your fish acting strange or are they healthy because if they are healthy I wouldn’t worry about it and your plants might just be dormant or building up enough strength to grow

Also what kind of fish do you have tank size and size of fish
I have had a few random deaths over the last month or so, from seemingly healthy fish. Everything else is acting normal, my severums and angels are breeding fairly often. All my loaches are nice and fat.

This is a 220g with a 40g sump. My severums are about 5" at this point
 
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