Odd die-off problem

[slick]

Hi all,

I've attached a photo of my tank before changing lights. It had been up about 4 months at that point and was starting to fill in, but some plants were not growing at all; swords, alternanthera. The lighting was 160 watts of regular T8 fluorescent bulbs of the garden centre "grow light" variety. Very cheap, but seemed to be working for the low demand plants at least.

Then I decided to bring my lighting in line with what I though it should be and installed 4 x 96 watt power compact fluorescent (384 watt total) at 6300K. This was about 6 months ago.

The initial result was an algae bloom covering the tank. Pretty aweful. Green algae, and some brown hair algae.

I picked off as much as I could, which wasn't enough to make a difference, and started "overdosing" with Excell as discussed in some other links here. The algae subsided, but so did the plants. Many died off. Others were just stunted.

I stopped the Excell, did massive water changes, and now the plants are showing some minor signs of improving, but are nothing like when I was using cheap low wattage light. Here's the summary:

Vals - doing well
Large swords - modest growth, holes in leaves.
Pigmy swords - stopped growing.
Alternanthera - dead
Java moss - dead
Java fern - stopped growing.
Red Lotus - modest growth.
Crypts wendii - no growth, maybe dying back still
Rotala - can't kill this stuff, but it's a weed, really.
Bacopa - starting to grow back, but all old stems will have to be cut back completely.

Perhaps it's all a coincidence, but it seems odd.

Water is RO, with RO-Right to hardness of about 5. PH maintained religiously at 6.5. Temp is 28 C / 89 F. Also has CO2 and substrate heating.

I've recently started adding micronutrients daily, which seems to help.

So the big questions are...

Was the lighting change a coincidence?
Was it the Excell that killed the plants along with the algae?
Why aren't the plants springing back?

Any help or insight is greatly appreciated.

[pcsb23]

Hi and welcome on board. It sounds as though you had/have two side of the triangle in place. Basically planted tanks are always a balancing act, get one bit out of balance and either the plants die or suffer and/or you get algae.

The lighting change wasn't a coincidence, indeed it was the cause. The reason is that with high output lights and lots of watts the plants grow quicker and use up the nutrients, macr and micro, very quickly. Normally its Carbon - in the form of CO2 normally - that limits as most don't use it. In your case the CO2 is there but no mention of fertilisers, and I don't mean excell as thats just another source of carbon. Seachem flourish is the sort of ferts I mean.

I'm reasonably sure that if you dose daily with ferts the plants will recover and flourish.

[Alight]

Flourish will kill or reduce the growth of mosses and some plants (riccia, Java ferns and some others) if used in overdose. I think Paul is also right, and some of your other plant problems were caused by low macros and/or micros. Check your P04 and K if you can. Iron could have been a problem and Calcium and Magnesium could also be a problem, since you are using pure RO and reconstituting. Most likely the Magnesium.

Check out plantedtank.net for much more info.

Al Light

[diablocanine]

IMHO, you might want to think about lowering your temps to around 84 also. Some of the plants you have listed do not do well at the temps you have, actually amazed the java fern and java moss lived as long as it did. I would guess the modest/no growth you are experiencing on some plants is due to lack of ferts. You have more than doubled you light intensity to 2.84 wpg over your tank. Although not considered high light it should work just fine. Are you using pressurized CO2? I would recommend putting fert balls in the substrate under the plants also. Much debate over the effectiveness of substrate heaters, but common sense tells me that if the ground is warmer, there is a greater need for ferts in the ground. I do not think the OD of excel was the reason for decline, I have read where many have used it effectively to control algae and not hurt their plants/fish. You were careful and did not dose more than triple strength daily, right?

[Dissident]

Plants need micro and macro neutriants to grow. You probably have a deficancy of all the major macros and micros.

Take some time and do some research to see what you need or just use this list:

Nirtates
Iron
Potassium
Phosphate
Calcium
Maginisum

Micro (Trace Elements)

Gregg Watson's site is a great resource for buying in bulk and will save you a ton of $$ in the long run.

Temp is very high for plants, 83-85F. Substrate heaters are a pain IMO and what type of CO2 system are u using?

[Alight]

Actually, 28 C is only about 82.4 F, so I don't believe temp was the problem, unless you were actually at 89 F. All of the plants you mentioned have done quite well in my planted Discus tank at 84-86 F.

As to Exel, the plantedtank.net forum has quite a bit of anecdotal evidence posts there that Excel overdose does kill or slow down many types of plants, particularly the mosses and ferns. It seems to kill algae first, then mosses, then riccia and jave ferns, and then other more complex plants, as the dose gets higher. However, there is no evidence that is kills off alternantha for Crypts.

Also, many members have noted the kill off of several varieties of fish, particularly algae eaters and loaches with overdose. This is, again, anecdotal, but probably the best info out there.

I have had no problem with 2X overdose killing fish, but my Discus did act stressed after a couple of weeks of this. They were off their feed, and less active, and didn't spawn like they ususally do. They're back to normal with the suggested dose of Excel without the large dosing suggested for water changes.

The Excel overdose also did kill my mosses, and did kill a few java ferns and slowed down their growth. Most of the other plants grew much faster and looked much better with this treatment. It initially got rid of the black beard algae, but it did come back. However, I just got my CO2 injection system, so hopefully, I can beat it back again with this.

[pcsb23]

I read the temp at 28C, which is the normal way I look at temps, didn't register the 89F, for what its worth 28C is 82F (give or take) this should not be a prob for plants. 89F could well be though (31C or there abouts).

One thing seems we all agree on is that the balance of ferts (macro and micro) is out of whack. This is wher I would start to concentrate on. The websites mentioned have loads of really good info.

[diablocanine]

Good catch, you know if I had a clue about the metric system maybe I would have noticed. 89F did get noticed.....DC

[Suzanne]

http://rexgrigg.com/./index.htm

[slick]

Thanks to all for the help so far.

Thanks especially for the temp correction. Yes, I live in Celcius-land, so it looks like my temp is good.

I used the Excell at 2x for about three weeks before giving up. There was clearly a decline in the algae, but at that point I started pulling the worst plants and if they still appeared to be salvagable I cleaned and replanted.

I've been using Flourish micronutrients. I "dose" daily. I put a generic pump-bottle top on, which dispenses about 3 ml (slightly over 1/2 tsp, and I double checked my conversion this time).

I haven't added macronutrients, but will to the research that was suggested.

My last questions for now are regarding the CO2. I use a fermenter with a store bought diffuser that seems to diffuse almost all the CO2, although perhaps 10% escapes. Is this simply not enough CO2? Is the inconsistency (more CO2 soon after recharge, less later in the week) causing a problem?

Thanks again.

[pcsb23]

The fermenter CO2 diffuser systems are just not man enough for a tank of your size, also the amount of CO2 they dispense is near impossible to control. They work adequatley for small setups but for big tanks, its best to get a bottle and regulator, also I would strongly advise a solenoid valve that links in wityh the lights. No need to produce CO2 at night, the plants give off plenty then!

[diablocanine]

The fermenter CO2 diffuser systems are just not man enough for a tank of your size, also the amount of CO2 they dispense is near impossible to control. They work adequatley for small setups but for big tanks, its best to get a bottle and regulator, also I would strongly advise a solenoid valve that links in wityh the lights. No need to produce CO2 at night, the plants give off plenty then!

ditto....DC

[nightowl1250]

Still a very nice planted tank :)

[slick]

Is there any potential problem of too much CO2? I know at the relatively high temperatures of a Discus tank both Oxygen and CO2 are less soluble, and I'm wondering if increasing the CO2 decreases disolved oxygen. I realize that if the CO2 is controlled properly this won't happen, but as a bottled CO2 neophyte I'm wondering how risky this is.

Cheers

[pcsb23]

The short answer is yes, but its worth an explanation! At lower ph's more CO2 will dissolve into the water, ultimately suffocating the fish, also with low levels of buffering you will get large ph swings, which will cause stress and lead to illness. However this is if you pile CO2 into the tank uncontrollably. With a proper setup it would take some sort of numpty to do that.

In all honesty the risk is minimal, start off slowly, and monitor as you slowly increase the amount you put in.

Although this link doesn't answer all questions there is some good info here:
http://forum.simplydiscus.com//showthread.php?t=36155
Take care,

[diablocanine]

Here is a chart to use after you have read that:

http://www.csd.net/~cgadd/aqua/art_plant_co2chart.htm

What is a numpty?

[Alight]

Started to answer this before Paul did.

The CO2 will not decrease your O2, and actually increases it in my tank due to the extensive "pearling" that the CO2 induces.

Too much CO2 can, of course, kill all your fish if it gets above 40 ppm. It can also cause very low pH if your water is not properly buffered.

Most pressure system CO2 users have a solenoid somewhere in the system that cuts off the CO2. Some control this with their light switch as plants actually make CO2 at night, so CO2 levels could get very high if the CO2 was not turned off.

Others have a pH detector control the solenoid. When the pH gets too low, the CO2 is cut off. This can, effectively, keep the CO2 constant at all times as the pH is directly related to the amount of CO2 dissolved in the water. This also (obviously) would prevent and bad pH swings from happening.

Most people also adjust their CO2 flow rate gradually upwards, as Paul suggests, and set it so that it can't go so high as to kill their fish, even if everything else fails.

As Paul says, these systems can be easily adjusted so that it takes some effort to kill your fish.

Al Light