Plant Issues - Algae?

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Aquarium Advice Newbie
Feb 16, 2022
Hello All,

New here to the Forum, however not to the aquatic fish and plant keeping world! I have been keeping fish, off and on for over 30 years. I have no issues with my fish’s health and in keeping general water parameters in check and employ various methods to do so. I started keeping planted tanks a few years back with the purchase of my 50 gallon. So I am not as experienced at keeping plants as I am fish, however they have never given me any grief, up until now. I will outline my tank set up first and then highlight the issue/issues I am having with pictures to Hopefully, someone more experienced with this, can provide some incite as to what might be happening to my plants. I have my own suspicions, and would love some feedback and possible solutions. Possibly different algae types and hopefully the, “One, Two Punch,” method might work for my situation?

75 Gallon Glass Top Tank
Dual 70 HOB Aqua Clear filters (filter media is, foam, filter fiber, crushed oyster shell, bio ceramic balls and Pothos plant roots in filter bag)
Pre filters on both inlets of HOB filters
Dual 300W heaters
One 48" Sunblaster LED full spectrum 6,400K lighting, 5,150 lumens, 48W, placed 2 inches above my glass aquarium hood, about 23 inches to substrate, giving around 70par. Plus the useless lighting that came with the tank, (not sure on brand or wattage, spectrum etc.., as no indicators and call to manufacturer did not garner any further information. Just know that it is ineffective, dim and vastly overpowered by my Sunblaster.
One large 6 inch air stone disk, set to about medium flow.
Hardscape comprised of rocks, wood, and plants.
River gravel over organic potting soil substrate, (same set up as last 50 gallon tank with no issues after established and ran for over 2 years.)
Pothos plants placed in both HOB filters.
Passive CO2 Bell - New bell is 12 inches high, 8 inches in diameter (upgrading to injected CO2 next week when the system arrives). Possibly currently about 10-15ppm in the tank? Not verified, as not registering on CO2 checker set for 30ppm. Some pearling was seen on some of the plants each day, since new bell installed two days ago on February 12th. Older bell was 11 inches high, by 3 inches in diameter. No pearling was ever witnessed, with the old bell in tank.
Crushed oyster shell (2 cups total split and placed into filter bags, in each of the HOB. Will be uping it to likely one more cup, as our water is farily soft here.
I add a small amount of tannins to the water, whenever I feel the need, based on tanks water color, (I like just a slight cast of it for my purposes).
I add a couple of tablespoons of aquarium salt after every water change.

Annubis Barteri, (petite, nana, sp.)
Cryptocoryne Undulata, (Broad leaf)
Echinodorus Grisebachii (Amazon Sword)
Ceratophyllum Demersum (Hornwort)
Alternanthera Reineckii (Pink)

3 Redline Sharks (full grown)
3 Flying Foxes (full grown)
2 Tiger Barbs (full grown)
5 Tiger Barbs - mixed green, albino and reg. tiger (small, growing)
5 Widow Tetras - mixed black and white (full grown)
2 Three Spot Gourami’s (full grown)
2 Golden Gourami’s (small, growing)
2 Koi Angels (small, growing)
8 Cherry Barbs (small, growing)
1 Black/Red Tail Shark (small, growing)
2 Electric Blue Acara’s (small growing)
1 Otocinclus (full grown, small)
2 Green Emerald Cory’s (full grown)
2 Salt & Pepper Cory’s (small growing)
5 Kuhli Loaches (full grown)
3 Asian Catfish (full grown??)
3 Skunk Botia (small, growing)
1 Striped Rafael Catfish (small, growing)
10 Mystery Snails - assorted, blue, black, orange and lavender (medium, growing)

I change the water every Wednesday night just before lights off.
I test the water three times a week, once before the water change, once the next day after water change and then again a few days before the next water change.
Always check the water parameters at the same time of day, before lights off.
I change at least 50% and closer to 60% of the water once a week and occasionally change 75%, if I feel parameters are too far out of line. I sometimes do a small 25% on Sundays, if I think the tank will not make it to water change day on Wednesday.
I change/clean the filter media and pre filters every second water change, (I do not clean the prefilters, foam filters or bio balls).
I do not run carbon in my filters, have not for over a year now.
Water is local dechlorinated tap water, pretty neutral and not very hard; which is why I add the crushed oyster shell.
Add Flourish Excel after water change, according to bottles instructions.
Add Tropica Specialised liquid fertilizer the morning after water changes and before lights go on, as per bottles instructions. Second dose on Sunday’s, (only started dosing twice a week two weeks ago, when I planted new plants). I will be switching over to Easy Green fertilizer once it arrives next week.
Add Seachem Iron once a week on second fertilizer day in Sunday, according to bottles instructions (have only been dosing this way for two weeks now).
Add Seachem Comprehensive once a week on second fertilizer day on Sunday, according to bottles instructions (have only been dosing this way for two weeks now).
Light cycle is 11 hours on.
Filters, set to max flow.
Air stone set to medium flow
Fill up CO2 bell before lights on (about an hour or so before and give only enough to end of light cycle).
Last plants added (Amazon Sword, Hornwort and Alternanthera Reineckii), was two weeks ago.
Last time I added new fish was over a month ago.
I do not over feed my fish. However, with as large a stock of fish as I have, I feed enough to keep everyone happy and still offer lighter feed days and an off feed day once a week (not scheduled, random).

Before Last Water Change (75%) - February 9th, 2022
Temp - 78F
PH - 7.4
Iron - .01 mg/l
Chlorine - 0 mg/l
KH - 60-80mg/l
GH - 50-60 mg/l
Ammonia - 0 ppm
Nitrites - 0 ppm
Nitrates - 40-60 ppm (always spikes a few days before water change day)

Water Test - February 10th, 2022
Temp - 78F
PH - 7.4
Iron - .01 mg/l
Chlorine - 0 mg/l
KH - 60-80mg/l
GH - 50-60 mg/l
Ammonia - 0 ppm
Nitrites - 0 ppm
Nitrates - 10-20 ppm

Last Water Test - February 13th, 2022
Temp - 78F
PH - 7.4
Iron - .01 mg/l
Chlorine - 0 mg/l
KH - 60-80mg/l
GH - 50-60 mg/l
Ammonia - 0.25 ppm (new spike) (has always been stable at 0 ppm after tank set up)
Nitrites - 0.25 ppm (new spike) (has always been stable at 0 ppm after tank set up)
Nitrates - 40-60 ppm (always spikes a few days before water change day)

I know I am overstocked with fish, for now (lol). Some of my fish are older and on the way out, most are small still growing and the rest are bottom dwellers. I have always overstocked and over filtered my tanks for various reasons; and without issues in the past. I also know that my Nitrate spikes are mainly related to my overstocking of fish. Or are they, (maybe my plants are not healthy enough at the moment to uptake this extra load, or are contributing to it with organic plant matter with die off)? I am setting up a 125 - 150 gallon tank this summer, when the temperatures outside are warmer and I can ship and move the tank without fear of breakage. I bought the new 75 gallon as a temporary winter weather solution to my smaller 50 gallon tank it replaced. I plan on making the 75 gallon into a tank for the breading of plants and fish, after I get the bigger tank going. I will be moving most (all?) of the fish on my list to this new tank. In the interim, I will not be replacing any of the older fish that die off, or adding any other additional fish before I get my new tank.

My problems arose, when I switched over to the new 75 gallon tank from the old 50 gallon. The new tank has been running since December 22nd, 2021. Old top river rock substrate (plus some new potting soil) and old filter media were used to establish the new 75 gallon tank. No issues noted with fish, or the plants at first, that is until about a week in and then my plants started to look like crap, (as indicated by the current pictures attached. My once beautiful two plus year old plants, including my slow growing, mature Annubis (that was regularly flowering), started to show signs of poor health. This was the first plant to show signs. It has gone downhill fast from there and I have been trying to find a solution/s ever since.

Now my Crypts, seem to be infected, and some leaves appear to be melting, or possibly rotting My Hornwort seems to be growing like a weed and unaffected at present. All of my Annubis plants are still putting out smaller leaves, although they seem smaller, paler perhaps, than before? Most of the mature leaves are curled with black edges and green blotches on them. My sword and Reineckii, seem to be okay, however it looks like whatever this is may be starting on them as well, (these two plants, were only planted about two weeks ago). Some of the Pothos plants new leaves have small holes in them, as well as some of the leaves on all the plants In the tank, except for the Hornwort. Looks like some melt, rot, curling going on as well, on all of the different type plants leaves, again except the Hornwort. I pulled out the worst of the Crypts leaves, as I am not worried about grow back with this faster growing plant, as it has always done well for me, up to now.

I called the tank manufacture to complain about the supplied lighting and they said it was not meant to grow plants. I then upgraded the crappy lights to the new Sunblaster LED full spectrum lighting about one month ago, thinking that was the problem (still not sure if this is/was, part of the problem). I have added a bigger CO2 bell on the weekend, thinking that was the problem, (too early to tell). Started dosing the Tropica Specialized fertilizer twice a week and added the extra Seachem trace elements and iron once a week on second fertilizer day on Sunday. I have been doing this new fertilizer routine for only two weeks now. I think I have (wishful placebo thinking?? noticed a small health improvement in the plants over the past few days. I am not sure it this is due to the most recent CO2 and fertilizer dosing changes. Reduced the lighting period from 12 hours on, to 11 hours a week ago and I plan to reduce to 10 hours on next week (already on 10 hours, started yesterday). I like making small changes, allowing time to study outcomes and noting the results. Easier to learn from this way and less stressful for all occupants of the tank, plant and fish.

I believe that I may be dealing with some type of type of diatom algae, GSA, or BSA, Crypt Rot, fertilizer issue, or perhaps all three issues now!!??? I did have BBA in the old 50 gallon tank back about a year and a half ago, after setting it up. I killed it off using the Flourish Excel overdose method and have not seen it since. Is this the remnants, and possibly a mutated version of that BBA? Will the,‘One, Two Punch” method work for this/these issue/s in my tank? Will adding the injected CO2 improve this situation, or make it worse? I plan on only supplementing CO2 at about 15-20ppm, would anyone advise more/less? Are my plants not healthy enough at the moment to uptake the extra Nitrates and possibly contributing to the problem with plant die off? Is this why I am seeing the Nitrate spikes each week? Is my tank lighting adequate enough? I would classify my tank as a medium level for both lighting and plant load, is that correct? Any issues with my current and planned fertilizer schedule, or advice offered? Do I need the extra trace and iron ferts? Are my new recent spikes in both Ammonia and Nitrites (have always been stable at 0 ppm after tank setup) in the last few days, possibly attributed to the new fertilizer schedule and CO2 increase? Is this a sign things are coming back online for the plants, or is this an ominous sign of bigger underlying issues now in the tank, or to come? Will the leaves on my Annubis recover, or best to cut the worst of them off now?

Any help, someone can give to an old fish keeper and new planted tank keeper, would be most awesomely appreciated! Sorry for the long post, I thought providing more information up front, might equal clearer and more concise responses and hopeful answers.

Please see attached pictures for reference. I have been taking shots of the plants every few days, to note any changes for the worse, or betterment.

Wishing All Universal Peace, Protection, Love, Light & Fish/Plant Keeping Heaven!


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Did you gradually change the lighting - starting from similar to what the old light was, and then increase it over time when you got the new light? It could be that the plants were shocked /burned by the new light?
I agree with your theory that a lot of things could be happening at the same time here

Just because you moved substrate from the other tank doesn’t mean you instantly cycled that tank completely. If anything disrupting an older substrate and moving it is probably going to set things back on the new tank. Uprooting and transplanting the plants tends to set them back a bit. Then of course with any new, in seasoned tank you’re going to have diatom/algae issues which surely doesn’t help the plants when that starts covering leaves. Then like Aiken stated, with this new light if you just cranked up the light intensity and hours (11hr is a long photo period, especially a newer setup) you can actually ‘burn’ the leaves if they’re used to lower light intensity. Then of course alot of light in an unseasoned tank = recipe for algae.

Basically, I’d almost have to say everything you’ve done is working against you.

I think you’re on the right track, reduce light hours (and intensity if you can with that light) and give those plants time to settle in. If they did get ‘burnt’ there will be a period of time where they are going to look ugly before they get better. Personally I think you’re going overkill on the fertilizers also, I only dose flourish and iron after a water change and mid week. But everyone has their theory on fertilizers, as long as you aren’t building up excess in the water and causing an algae bloom you’re just wasting more than you are hurting anything

That’s not the worlds most powerful light, but it’s still a decent amount of light. I grow plants just fine (other than my dud scarlet) in my 75g with a 2400 lumen light
This is the easiest way to figure out whats what.

Look at your Pothos. Does it look
Deficient? If the answer is no then obviously the tank has plenty of nutrients. What does the Pothos have access to that the underwater plants are starving for? Carbon Dioxide.

You are obviously achieving some co2 though with your current setup and the bell method plus your stocking. Light drives co2 demand up and thats quite a powerful light which is on for approximately double the par and on for double the amount of time the average high tech keeper will use. Thats with injected co2 perfectly distributed.

Plants that have been grown out of water react violently when first submerged. They NEED to shed leaves because their old leaves are suited to emersed conditions so melting is normal. The issue is that once plants melt and you have lots of light and an abundance of nutrients in a new tank you get algae and lots of it. But this happens to 95% of new high tech tanks. In order to get algae under control you need an established biological filter.

First things first, reduce you lighting schedule to 8 hours and if it has a power control turn it down a couple of notches or if possible raise the fixture. Lets see what less light does. You certainly do not have too little I can assure you.
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