Question:
I have a 46-gallon bow front freshwater aquarium and have a few questionsabout lighting and replacing water using a tap water filter.

Fist, I seem to have a problem growing certain plants, especially ones inthe foreground. I have a coralife 192-watt compact fluorescent light, 6700k.Which should be sufficient for any high light plant, right? I purchased thestands for the light housing but I'm not sure it would help to offset thelight 2" off the top or not? The tank is bowed, so maybe that is why I havea problem growing plants in the foreground. I have two one-gallon glass jugsfor DIY Co2 as well, with the tubing routing through the intake of mycanister filter. One of the plants I am talking about is; Microsword-lilaeopsis (looks like grass) I have standard gravel and some lateritemixed in as well. The grass just seems to grow algae and die off. My waterparameters are, PH 6.5, ammonia is good, nitrite is good, and water hardnessis low.

Second, the way I filter my water is with a "tap water filter" by aquariumpharmaceuticals. I was wondering if there was a cheaper alternative tofilter tap water other than purchasing a replacement filter every month. Ihave been looking at the RO filters, like the deluxe maxxima 35 HI-S by KentMarine. Would something like that save money later on down the road? Orshould I keep on buying the tap water filter replacements? My tap water outof the faucet is very hard and high in PH.

I have a tap filter, a Pur, and there are many ppl who have tried, but thatdoesn't really make water 'safe' for fish, it only take out some thingsusing salts, and you'll basically wear it out prematurely.... Get someWardley's Chlor out and or Prime, AmQuel or something and use it as a waterconditioner.... it's ok to use RO/DI, but you'll have to supplement to addthe stuff that is taken out with RODI water... again, not an expert, butyou're so close, be patient, wait for Chuck Gadd, Dave Milman, NetMax andothers to chime in, they ARE the experts... I just play one on thewebsites.... hahaha...

Answer: 1/2 this lighting will grow _any_ plant I know of.The issue is too much lighting likely. But we can figure out what youneed to do about it.

This has not been a problem for several large bow fronts I've set upover the years, they had massive fields of Gloss that did fine with1/3-1/2 this lighting.

Well at high light you place more demand on the CO2, DIY CO2 + over 4watts gal of lighting is a BAD combination, you should have gotten theGas tank CO2 first,before the high lighting.CO2 is your weak link here and you need to either keep up on the DIYand work at getting it to maintain enough CO2, 20-30ppm the entiretime the lights are or use gas tank CO2.

Sure, use tap water. The tap water is fine for plants, you migfht wantsoft water for only certain species of fish, but what is wrong withthe tap water that makes you use tap water filters or want to use RO?

I'll tell you this, you are not helping the plants by doing this, CO2is what they are concerned about, soft vs hard water makes nodifference in plant growth. This is myth that plants prefer softwater.

I have been looking at the RO filters, like the

But you use CO2, it makes no difference as far as the plants areconcerned.I've got pictures in TFH with very hard tap water plant tanks, KH 10 ,GH 24 etc.Plants grow fine if you add enough GH/KH roughly 3, but I do not knowof any upper limits, some folks do fine at 20KH and I know from yearsof growing at 10KH, 24GH, high GH seems to help more than anything,not harm plants in any way.

It's all about the CO2, if you want to save $, buy an CO2 system, youdo not need a RO for helping plants grow better. I've only seen acouple of cases where it was well water with high salt content andonce with high copper in their pipes/supply etc. But barring thesevery rare exceptions, it's a myth soft water helps plant growth.

Now your fish might prefer softer water, but the plant could careless.I've had and used both hard and soft water with some 250+ species ofaquatic plants. Buy the Gas CO2 or keep up on the DIY. Use plain tapwater, adjust the pH using only CO2 gas to get a CO2 level of 20-30ppmduring the entire light cycle.see the pH/KH/CO2 table to determine the CO2 by measuring the KHfirst, then seeing what pH you'll need to get a CO2 level of 20-30ppm.Use only CO2 gas to change the pH, this is what the plants want, notsoft water/low pH etc.